Novel proteins specific for calcitonin gene-related peptide

ABSTRACT

The present disclosure provides hNGAL muteins that bind CGRP and can be used in various application including pharmaceutical applications, for example, migraine. The present disclosure also concerns methods of making one or more muteins described herein as well as compositions and combinations comprising one or more of such muteins. The present disclosure further relates to nucleic acid molecules encoding such muteins and to methods for generation of such muteins and nucleic acid molecules. In addition, the application discloses therapeutic and/or diagnostic uses of these muteins as well as compositions and combinations comprising one or more of such muteins

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Application No.62/265,792, filed Dec. 10, 2015, the entire content of which isincorporated herein by reference.

The instant application contains a Sequence Listing which has beensubmitted in ASCII format via EFS-WEB and is hereby incorporated byreference in its entirety. Said ASCII copy, created on Nov. 29, 2016, isnamed sequence.txt and is 119 KB.

I. BACKGROUND

Calcitonin gene-related peptide (CGRP) is a vasoactive neuropeptidesecreted by the nerves of the central and peripheral nervous systems,where CGRP-containing neurons are closely associated with blood vessels.CGRP-mediated vasodilatation is also associated with neurogenicinflammation, as part of a cascade of events that results inextravasation of plasma and vasodilatation of the microvasculature andis present in migraines.

CGRP exists as highly homologous α and β isoforms in both human and ratalthough each is encoded by a distinct gene. The α and β isoforms of theCGRP peptides differ by three amino acids in humans and one amino acidin rats. The amino acid sequences of CGRP peptides are well conservedamong species and are considered members of a family of peptides thatincludes amylin, calcitonin, and adrenomedullin.

CGRP is thus divided into at least two subtypes, denoted as α-CGRP orCGRP1 and β-CGRP or CGRP2 (Pharmacol. Rev 54:233-246, 2002). Theexistence of at least two CGRP subtypes had been proposed fromdifferential antagonist affinities and agonist potencies in a variety ofin vivo and in vitro bioassays. (Dennis et al., hCGRP8-37, A calcitoningene-related peptide antagonist revealing calcitonin gene-relatedpeptide receptor heterogeneity in brain and periphery, J. Pharmacol.Exp. Ther., 254:123-128 (1990); Dennis et al., Structure-activityprofile of calcitonin gene-related peptide in peripheral and braintissues. Evidence for receptor multiplicity, J. Pharmacol. Exp. Ther.,251:718-725 (1989); Dumont et al., A potent and selective CGRP agonist,[Cys(Et)2,7]hCGRP alpha: comparison in prototypical CGRP1 and CGRP2 invitro bioassays, Can. J. Physiol. Pharmacol, 75:671-676 (1997)).

The CGRP1 subtype was found to be sensitive to the antagonist fragmentCGRP(8-37). (Chiba et al., Calcitonin gene-related peptide receptorantagonist human CGRP- (8-37), Am. J. Physiol, 256:E331-E335 (1989);Dennis et al (1990); Mimeault et al, Comparative affinities andantagonistic potencies of various human calcitonin gene-related peptidefragments on calcitonin gene-related peptide receptors in brain andperiphery, J. Pharmacol. Exp. Ther., 258:1084-1090 (1991)). By contrast,the CGRP was sensitive to linear human CGRP (hCGRP) analogs, in whichthe cysteine residues at positions 2 and 7 were derivatized (e.g., withacetoaminomethyl [Cys(ACM)2′7] or ethylamide [Cys(Et)2′7]) but CGRPreceptor was insensitive to fragment CGRP(8-37). (Dennis et al (1989);Dennis et al (1990); Dumont et al (1997)). Three calcitonin receptorstimulating peptides (CRSPs) have also been identified in a number ofmammalian species; the CRSPs may form a new subfamily in the CGRPfamily. (Katafuchi, T and Minamino, N, Structure and biologicalproperties of three calcitonin receptor-stimulating peptides, novelmembers of the calcitonin gene-related peptide family, Peptides,25(11):2039-2045 (2004)).

CGRP mediates its effects through a heteromeric receptor composed of a Gprotein-coupled receptor called calcitonin receptor-like receptor(CALCRL) and a receptor activity-modifying protein (RAMP1). CGRPreceptors have been identified and pharmacologically evaluated inseveral tissues and cells, including brain, cardiovascular, endothelialand smooth muscle. Multiple CGRP receptors have been characterized basedon distinct pharmacological properties. The calcitonin superfamilypeptides act through seven-transmembrane-domain G-protein-coupledreceptors (GPCRs). The calcitonin receptor (“CT”, “CTR” or “CTreceptor”) and CGRP receptors are type II (“family B”) GPCRs, whichfamily includes other GPCRs that recognize regulatory peptides such assecretin, glucagon and vasoactive intestinal polypeptide (VIP). The bestcharacterized splice variants of human calcitonin receptor differdepending on the presence (formerly CTRn+ or CTRI, now known asCT{circumflex over ( )})) or absence (the major splice variant, formerlyCTRπ_ or CTR2, now known as CT(a)) of 16 amino acids in the firstintracellular loop. (Gorn et al., Expression of two human skeletalcalcitonin receptor isoforms cloned from a giant cell tumor of bone: thefirst intracellular domain modulates ligand binding and signaltransduction, J. Clin. Invest., 95:2680-2691 (1995); Hay et al., Amylinreceptors: molecular composition and pharmacology, Biochem. Soc. Trans.,32:865-867 (2004); Poyner et al., 2002).

CGRP is widely distributed in sensory nerves, both in the peripheral andcentral nervous system and displays a large number of differentbiological activities. When released from trigeminal and other nervefibers, CGRP is thought to mediate its biological responses by bindingto specific cell surface receptors. The biological activities of CGRPinclude the regulation of neuromuscular junctions, of antigenpresentation within the immune system, of vascular tone and of sensoryneurotransmission. (Poyner, D. R., Calcitonin gene-related peptide:multiple actions, multiple receptors, Pharmacol. Ther., 56:23-51 (1992);Muff et al., Calcitonin, calcitonin gene-related peptide, adrenomedullinand amylin: homologous peptides, separate receptors and overlappingbiological actions, Eur. J. Endocrinol., 133: 17-20 (1995)).

There is a great need, therefore, to identify new compounds thatspecifically recognize and bind CGRP. Such compounds would be useful fordiagnostic screening and therapeutic intervention in disease states thatare associated with CGRP activity. Accordingly, it is an object of thepresent disclosure to provide specific binding compounds of CGRP formodulating CGRP activity. Such compounds disclosed herein take the formof muteins derived from human lipocalin 2 (also known as neutrophilgelatinase associated lipocalin, “hNGAL”).

II. DEFINITIONS

The following list defines terms, phrases, and abbreviations usedthroughout the instant specification. All terms listed and definedherein are intended to encompass all grammatical forms.

As used herein, “CGRP”, unless specified as being from a non-humanspecies (e.g., “rat CGRP,” “monkey CGRP,” etc.), means human α-CGRPand/or human β-CGRP.

As used herein, “α-CGRP” or “alpha CGRP”, unless specified as being froma non-human species (e.g., “rat α-CGRP,” “monkey α-CGRP,” etc.), meanshuman CGRP1, a full-length protein defined by Swiss Prot P06881 or abiologically active fragment thereof (e.g., a fragment of the CGRP1protein which is capable of inducing plasma protein extravasation invitro or in vivo).

As used herein, “β-CGRP” or “beta CGRP”, unless specified as being froma non-human species (e.g., “rat β-CGRP,” “monkey β-CGRP,” etc.), meanshuman CGRP2, a full-length protein defined by Swiss Prot P10092 or abiologically active fragment thereof (e.g., a fragment of the CGRP2protein which is capable of inducing plasma protein extravasation invitro or in vivo).

As used herein, “rat CGRP” means rat α-CGRP and/or rat β-CGRP. Ratα-CGRP (alpha CGRP) or rat CGRP1 is a full-length protein defined bySwiss Prot P01256 or a biologically active fragment thereof. Rat β-CGRP(beta CGRP) or rat CGRP2 is a full-length protein defined by Swiss ProtP10093 or a biologically active fragment thereof.

As used herein, “detectable affinity” means the ability to bind to aselected target with an affinity constant of generally at least about10⁻⁵ M or below. Lower affinities are generally no longer measurablewith common methods such as ELISA and therefore of secondary importance.

As used herein, “binding affinity” of a protein of the disclosure (e.g.a mutein of human lipocalin 2) to a selected target (in the presentcase, CGRP), can be measured (and thereby KD values of a mutein-ligandcomplex be determined) by a multitude of methods known to those skilledin the art. Such methods include, but are not limited to, fluorescencetitration, direct ELISA, competition ELISA, calorimetric methods, suchas isothermal titration calorimetry (ITC), and surface plasmon resonance(SPR). Such methods are well established in the art and examples thereofare also detailed below.

It is also noted that the complex formation between the respectivebinder and its ligand is influenced by many different factors such asthe concentrations of the respective binding partners, the presence ofcompetitors, pH and the ionic strength of the buffer system used, andthe experimental method used for determination of the dissociationconstant K_(D)(for example fluorescence titration, direct ELISA,competition ELISA or SPR, just to name a few) or even the mathematicalalgorithm which is used for evaluation of the experimental data.

Therefore, it is also clear to the skilled person that the K_(D) values(dissociation constant of the complex formed between the respectivebinder and its target/ligand) may vary within a certain experimentalrange, depending on the method and experimental setup that is used fordetermining the affinity of a particular mutein for a given ligand. Thismeans that there may be a slight deviation in the measured K_(D) valuesor a tolerance range depending, for example, on whether the K_(D) valuewas determined by SPR, by competition ELISA, or by direct ELISA.

As used herein, a compound such as a mutein of the disclosure“specifically binds” a target (for example, CGRP) or has “bindingspecificity” for a target if it is able to discriminate between thattarget and one or more reference targets, since binding specificity isnot an absolute, but a relative property. “Specific binding” can bedetermined, for example, in accordance with Western blots, ELISA-, RIA-,ECL-, IRMA-tests, IHC and peptide scans.

The term “human lipocalin 2” or “human Lcn 2” or “human NGAL” or “hNGAL”as used herein refers to the mature human neutrophilgelatinase-associated lipocalin (NGAL) with the SWISS-PROT/UniProt DataBank Accession Number P80188. A human lipocalin 2 mutein of thedisclosure may also be designated herein as “an hNGAL mutein”. The aminoacid sequence shown in SWISS-PROT/UniProt Data Bank Accession NumberP80188 may be used as a preferred “reference sequence”, more preferablythe amino acid sequence shown in SEQ ID NO: 1 is used as referencesequence.

As used herein, a “mutein,” a “mutated” entity (whether protein ornucleic acid), or “mutant” refers to the exchange, deletion, orinsertion of one or more nucleotides or amino acids, compared to thenaturally occurring (wild-type) nucleic acid or protein “reference”scaffold. The term “mutein,” as used herein, also includes itsfunctional fragments or variants. Fragments or variants of particularmuteins described in the present disclosure preferably retain thefunction of binding to CGRP, e.g. with detectable or even higheraffinity, and such fragments or variants are “functional fragments orvariants” of the reference mutains disclosed herein.

The term “fragment” as used herein in connection with the muteins of thedisclosure relates to proteins or peptides derived from full-lengthmature human lipocalin 2 that are N-terminally and/or C-terminallyshortened, i.e. lacking at least one of the N-terminal and/or C-terminalamino acids. Such fragments may include at least 10, more such as 20 or30 or more consecutive amino acids of the primary sequence of the maturehuman lipocalin 2 and are usually detectable in an immunoassay of themature human lipocalin 2.

In general, the term “fragment”, as used herein with respect to thecorresponding protein ligand of a mutein of the disclosure or of thecombination according to the disclosure, relates to N-terminally and/orC-terminally shortened protein or peptide ligands, which retain thecapability of the full length ligand to be recognized and/or bound by amutein according to the disclosure.

The term “mutagenesis” as used herein means that the experimentalconditions are chosen such that the amino acid naturally occurring at agiven sequence position of the mature human lipocalin 2 can besubstituted by at least one amino acid that is not present at thisspecific position in the respective natural polypeptide sequence. Theterm “mutagenesis” also includes the (additional) modification of thelength of sequence segments by deletion or insertion of one or moreamino acids. Thus, it is within the scope of the disclosure that, forexample, one amino acid at a chosen sequence position is replaced by astretch of three random mutations, leading to an insertion of two aminoacid residues compared to the length of the respective segment of thewild type protein. Such an insertion or deletion may be introducedindependently from each other in any of the peptide segments that can besubjected to mutagenesis in the disclosure.

The term “random mutagenesis” means that no predetermined single aminoacid (mutation) is present at a certain sequence position but that atleast two amino acids can be incorporated with a certain probability ata predefined sequence position during mutagenesis.

“Identity” is a property of sequences that measures their similarity orrelationship. The term “sequence identity” or “identity” as used in thepresent disclosure means the percentage of pair-wise identicalresidues—following (homologous) alignment of a sequence of a polypeptideof the disclosure with a sequence in question—with respect to the numberof residues in the longer of these two sequences. Sequence identity ismeasured by dividing the number of identical amino acid residues by thetotal number of residues and multiplying the product by 100.

The term “homology” is used herein in its usual meaning and includesidentical amino acids as well as amino acids which are regarded to beconservative substitutions (for example, exchange of a glutamate residueby an aspartate residue) at equivalent positions in the linear aminoacid sequence of a polypeptide of the disclosure (e.g., any mutein ofthe disclosure).

The percentage of sequence homology or sequence identity can, forexample, be determined herein using the program BLASTP, version blastp2.2.5 (Nov. 16, 2002; cf. Altschul, S. F. et al. (1997) Nucl. Acids Res.25, 3389-3402). In this embodiment the percentage of homology is basedon the alignment of the entire polypeptide sequences (matrix: BLOSUM 62;gap costs: 11.1; cutoff value set to 10) including the propeptidesequences, preferably using the wild type protein scaffold as referencein a pairwise comparison. It is calculated as the percentage of numbersof “positives” (homologous amino acids) indicated as result in theBLASTP program output divided by the total number of amino acidsselected by the program for the alignment.

Specifically, in order to determine whether an amino acid residue of theamino acid sequence of a mutein different from the wild-type humanlipocalin 2 corresponds to a certain position in the amino acid sequenceof the wild-type human lipocalin 2, a skilled artisan can use means andmethods well-known in the art, e.g., alignments, either manually or byusing computer programs such as BLAST2.0, which stands for Basic LocalAlignment Search Tool or ClustalW or any other suitable program which issuitable to generate sequence alignments. Accordingly, the wild-typehuman lipocalin 2 can serve as “subject sequence” or “referencesequence”, while the amino acid sequence of a mutein different from thewild-type human lipocalin 2 described herein serves as “query sequence”.The terms “reference sequence” and “wild type sequence” are usedinterchangeably herein.

“Gaps” are spaces in an alignment that are the result of additions ordeletions of amino acids. Thus, two copies of exactly the same sequencehave 100% identity, but sequences that are less highly conserved, andhave deletions, additions, or replacements, may have a lower degree ofsequence identity. Those skilled in the art will recognize that severalcomputer programs are available for determining sequence identity usingstandard parameters, for example Blast (Altschul, et al. (1997) NucleicAcids Res. 25, 3389-3402), Blast2 (Altschul, et al. (1990) J. Mol. Biol.215, 403-410), and Smith-Waterman (Smith, et al. (1981) J. Mol. Biol.147, 195-197).

The term “variant” as used in the present disclosure relates toderivatives of a protein or peptide that include modifications of theamino acid sequence, for example by substitution, deletion, insertion orchemical modification. Such modifications do in some embodiments notreduce the functionality of the protein or peptide. Such variantsinclude proteins, wherein one or more amino acids have been replaced bytheir respective D-stereoisomers or by amino acids other than thenaturally occurring 20 amino acids, such as, for example, ornithine,hydroxyproline, citrulline, homoserine, hydroxylysine, norvaline.However, such substitutions may also be conservative, i.e. an amino acidresidue is replaced with a chemically similar amino acid residue.Examples of conservative substitutions are the replacements among themembers of the following groups: 1) alanine, serine, and threonine; 2)aspartic acid and glutamic acid; 3) asparagine and glutamine; 4)arginine and lysine; 5) isoleucine, leucine, methionine, and valine; and6) phenylalanine, tyrosine, and tryptophan.

By a “native sequence” human lipocalin 2 is meant human lipocalin 2 thathas the same amino acid sequence as the corresponding polypeptidederived from nature. Thus, a native sequence human lipocalin 2 can havethe amino acid sequence of the respective naturally-occurring humanlipocalin 2. Such native sequence polypeptide can be isolated fromnature or can be produced by recombinant or synthetic means. The term“native sequence” polypeptide specifically encompassesnaturally-occurring truncated or secreted forms of the human lipocalin2, naturally-occurring variant forms such as alternatively spliced formsand naturally-occurring allelic variants of human lipocalin 2. Apolypeptide “variant” means a biologically active polypeptide having atleast about 50%, 60%, 70%, 80% or at least about 85% amino acid sequenceidentity with the native sequence polypeptide. Such variants include,for instance, polypeptides in which one or more amino acid residues areadded or deleted at the N- or C-terminus of the polypeptide. Generally avariant has at least about 70%, including at least about 80%, such as atleast about 85% amino acid sequence identity, including at least about90% amino acid sequence identity or at least about 95% amino acidsequence identity with the native sequence polypeptide.

The term “position” when used in accordance with the disclosure meansthe position of either an amino acid within an amino acid sequencedepicted herein or the position of a nucleotide within a nucleic acidsequence depicted herein. To understand the term “correspond” or“corresponding” as used herein in the context of the amino acid sequencepositions of one or more muteins, a corresponding position is not onlydetermined by the number of the preceding nucleotides/amino acids.Accordingly, the position of a given amino acid in accordance with thedisclosure which may be substituted may vary due to deletion or additionof amino acids elsewhere in a (mutant or wild-type) human lipocalin 2.Similarly, the position of a given nucleotide in accordance with thepresent disclosure which may be substituted may vary due to deletions oradditional nucleotides elsewhere in a mutein or wild type humanlipocalin 2 5′-untranslated region (UTR) including the promoter and/orany other regulatory sequences or gene (including exons and introns).

Thus, for a corresponding position in accordance with the disclosure, itis preferably to be understood that the positions of nucleotides/aminoacids may differ in the indicated number than similar neighbouringnucleotides/amino acids, but said neighbouring nucleotides/amino acids,which may be exchanged, deleted, or added, are also comprised by the oneor more corresponding positions.

In addition, for a corresponding position in a mutein based on areference scaffold in accordance with the disclosure, it is preferablyto be understood that the positions of nucleotides/amino acids arestructurally corresponding to the positions elsewhere in a mutein orwild-type human lipocalin 2, even if they may differ in the indicatednumber.

The term “organic molecule” or “small organic molecule” as used hereinfor the non-natural target denotes an organic molecule comprising atleast two carbon atoms, but preferably not more than 7 or 12 rotatablecarbon bonds, having a molecular weight in the range between 100 and2000 Dalton, preferably between 100 and 1000 Dalton, and optionallyincluding one or two metal atoms.

The word “detect”, “detection”, “detectable” or “detecting” as usedherein is understood both on a quantitative and a qualitative level, aswell as a combination thereof. It thus includes quantitative,semi-quantitative and qualitative measurements of a molecule ofinterest.

A “subject” is a vertebrate, preferably a mammal, more preferably ahuman. The term “mammal” is used herein to refer to any animalclassified as a mammal, including, without limitation, humans, domesticand farm animals, and zoo, sports, or pet animals, such as sheep, dogs,horses, cats, cows, rats, pigs, apes such as cynomolgus monkeys andetc., to name only a few illustrative examples. Preferably, the mammalherein is human.

An “effective amount” is an amount sufficient to effect beneficial ordesired results. An effective amount can be administered in one or moreadministrations.

A “sample” is defined as a biological sample taken from any subject.Biological samples include, but are not limited to, blood, serum, urine,feces, semen, or tissue.

The term “metastasis” according to the disclosure refers to thetransmission of cancerous cells from the primary tumor to one or moresites elsewhere in a patient where secondary tumors develop. Means todetermine if a cancer has metastasized are known in the art and includebone scan, chest X-ray, CAT scan, MRI scan, and tumor marker tests. Theterm “prevention of metastasis” means that the metastasis of theprimary, tumor or cancer is prevented, delayed, or reduced and thus thedevelopment of secondary tumors is prevented, delayed, or reduced.Preferably the metastasis i.e secondary tumors of the lung are preventedor reduced, which means that metastatic transmission of cancerous cellsfrom the primary tumor to the lung is prevented or reduced.

The term “cancer” as used herein refers to proliferative diseases, suchas lymphomas, lymphocytic leukemias, lung cancer, non-small cell lung(NSCL) cancer, bronchioloalviolar cell lung cancer, bone cancer,pancreatic cancer, skin cancer, cancer of the head or neck, cutaneous orintraocular melanoma, uterine cancer, ovarian cancer, rectal cancer,cancer of the anal region, stomach cancer, gastric cancer, colon cancer,breast cancer, uterine cancer, carcinoma of the fallopian tubes,carcinoma of the endometrium, carcinoma of the cervix, carcinoma of thevagina, carcinoma of the vulva, Hodgkin's Disease, cancer of theesophagus, cancer of the small intestine, cancer of the endocrinesystem, cancer of the thyroid gland, cancer of the parathyroid gland,cancer of the adrenal gland, sarcoma of soft tissue, cancer of theurethra, cancer of the penis, prostate cancer, cancer of the bladder,cancer of the kidney or ureter, renal cell carcinoma, carcinoma of therenal pelvis, mesothelioma, hepatocellular cancer, biliary cancer,neoplasms of the central nervous system (CNS), spinal axis tumors, brainstem glioma, glioblastoma multiforme, astrocytomas, schwanomas,ependymonas, medulloblastomas, meningiomas, squamous cell carcinomas,pituitary adenoma and Ewings sarcoma, including refractory versions ofany of the above cancers, or a combination of one or more of the abovecancers.

The term “vascular diseases” includes Cancer, Inflammatory diseases,Atherosclerosis, Ischemia, Trauma, Sepsis, chronic obstructive pulmonarydisease (COPD), Asthma, Diabetes, age-related macular degeneration(AMD), Retinopathy, Stroke, Adipositas, Acute lung injury, Hemorrhage,Vascular leak e.g. Cytokine induced, Allergy, Graves' Disease,Hashimoto's Autoimmune Thyroiditis, Idiopathic Thrombocytopenic Purpura,Giant Cell Arteritis, Rheumatoid Arthritis, Systemic Lupus Erythematosus(SLE), Lupus Nephritis, Crohn's Disease, Multiple Sclerosis, UlcerativeColitis, especially to solid tumors, intraocular neovascular syndromes(such as proliferative retinopathies or AMD), rheumatoid arthritis, andpsoriasis (Folkman, J., et al., J. Biol. Chem. 267 (1992) 10931-10934;Klagsbrun, M., et al., Annu. Rev. Physiol. 53 (1991) 217-239; andGarner, A., Vascular diseases, In: Pathobiology of ocular disease, Adynamic approach, Garner, A., and Klintworth, G. K. (eds.), 2nd edition,Marcel Dekker, New York (1994), pp 1625-1710).

The term “antibody”, as used herein, is intended to refer toimmunoglobulin molecules comprising four polypeptide chains, two heavy(H) chains and two light (L) chains interconnected by disulfide bonds,as well as multimers thereof (e.g., IgM). Each heavy chain comprises aheavy chain variable region (abbreviated herein as HCVR or V_(H)) and aheavy chain constant region. The heavy chain constant region comprisesthree domains, C_(H)1, C_(H)2 and C_(H)3. Each light chain comprises alight chain variable region (abbreviated herein as LCVR or V_(L)) and alight chain constant region. The light chain constant region comprisesone domain (C_(L)1). The V_(H) and V_(L) regions can be furthersubdivided into regions of hypervariability, termed complementaritydetermining regions (CDRs), interspersed with regions that are moreconserved, termed framework regions (FR). Each V_(H) and V₁ is composedof three CDRs and four FRs, arranged from amino-terminus tocarboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3,CDR3, FR4. In different embodiments of the disclosure, the FRs of theanti-CGRP antibody (or antigen-binding portion thereof) may be identicalto the human germline sequences, or may be naturally or artificiallymodified. An amino acid consensus sequence may be defined based on aside-by-side analysis of two or more CDRs.

The term “antibody,” as used herein, also includes antigen-bindingfragments of full antibody molecules. The terms “antigen-bindingportion” of an antibody, “antigen-binding fragment” of an antibody, andthe like, as used herein, include any naturally occurring, enzymaticallyobtainable, synthetic, or genetically engineered polypeptide orglycoprotein that specifically binds an antigen to form a complex.Antigen-binding fragments of an antibody may be derived, e.g., from fullantibody molecules using any suitable standard techniques such asproteolytic digestion or recombinant genetic engineering techniquesinvolving the manipulation and expression of DNA encoding antibodyvariable and optionally constant domains. Such DNA is known and/or isreadily available from, e.g., commercial sources, DNA libraries(including, e.g., phage-antibody libraries), or can be synthesized. TheDNA may be sequenced and manipulated chemically or by using molecularbiology techniques, for example, to arrange one or more variable and/orconstant domains into a suitable configuration, or to introduce codons,create cysteine residues, modify, add or delete amino acids, etc.Non-limiting examples of antigen-binding fragments include: (i) Fabfragments; (ii) F(ab′)₂ fragments; (iii) Fd fragments; (iv) Fvfragments; (v) single-chain Fv (scFv) molecules; (vi) dAb fragments; and(vii) minimal recognition units consisting of the amino acid residuesthat mimic the hypervariable region of an antibody (e.g., an isolatedcomplementarity determining region (CDR)). Other engineered molecules,such as diabodies, triabodies, tetrabodies and minibodies, are alsoencompassed within the expression “antigen-binding fragment,” as usedherein. An antigen-binding fragment of an antibody will typicallycomprise at least one variable domain. The variable domain may be of anysize or amino acid composition and will generally comprise at least oneCDR which is adjacent to or in frame with one or more frameworksequences. In antigen-binding fragments comprising a V_(H) domainassociated with a V_(L) domain, the V_(H) and V_(L) domains may besituated relative to one another in any suitable arrangement. Forexample, the variable region may be dimeric and contain V_(H)-V_(H),V_(H)-V_(L) or V_(L)-V_(L) dimers. Alternatively, the antigen-bindingfragment of an antibody may contain a monomeric V_(H) or V_(L) domain.

III. DESCRIPTIONS OF FIGURES

FIG. 1: shows binding of selected CGRP-specific lipocalin muteins (SEQID NOs: 2 to 6) to human and to rat CGRP alpha and beta as measured in asolution binding competition ELISA. Muteins bind to all four CGRPspecies with low nanomolar to double digit nanomolar EC50 values, exceptfor SEQ ID NO: 3 and SEQ ID NO: 6 having lower affinity to rat alpha andhuman beta CGRP, respectively. The resulting EC50 values are summarizedin Table 1 of Example 4.

FIGS. 2A, 2B, 2C and 2D provide typical measurements of on-rate andoff-rate by SPR for the lipocalin muteins SEQ ID NO: 4, SEQ ID NOs: 7 to17, and SEQ ID NOs: 19 to 28. The association rates (ka), thedissociation rates (kd) and the resulting dissociation constants (KD) tohuman and rat CGRP species (alpha and beta), respectively, aresummarized in Table 2 of Example 5.

FIGS. 3A, 3B, 3C and 3D are graphical representations of the functionalactivity of selected CGRP-specific lipocalin muteins. The binding of thelipocalin muteins to CGRP leads to reduction of CGRP-induced cAMPproduction by SK-N-MC cells (human brain neuroepithelioma) or by L6cells (rat skeletal muscle myoblasts) for human and rat CGRP species(alpha and beta), respectively. The IC50 values for all four CGRPspecies are in the subnanomolar to low nanomolar range and aresummarized in Table 3 of Example 6.

FIGS. 4A and 48 show the inhibition of human alpha and beta CGRP-inducedcAMP production by SK-N-MC cells (human brain neuroepithelioma) throughbinding of CGRP-specific muteins, from which the natural occurringcysteine bridge was removed by protein-engineering. The IC50 values ofthe cysteine-free muteins (SEQ ID NOs: 29 to 40) remain unaffectedcompared to those of their respective parental muteins with the cysteinebridge (SEQ ID NO: 17 and SEQ ID NO: 27) and are summarized in Table 4of Example 7.

FIG. 5: provides typical measurements of on-rate and off-rate by SPR forthe lipocalin muteins (SEQ ID NOs: 87 to 93). The resulting dissociationconstants (KD) to human alpha CGRP are summarized in Table 5 of Example9.

IV. DETAILED DESCRIPTION OF THE DISCLOSURE

The current disclosure provides a polypeptide having binding specificityfor CGRP, wherein the polypeptide comprises an hNGAL mutein that bindsCGRP with detectable affinity.

In some embodiments, an hNGAL mutein binding CGRP with detectableaffinity may include at least one amino acid substitution of a nativecysteine residue by another amino acid, for example, a serine residue.In some other embodiments, a mutein binding CGRP with detectableaffinity may include one or more non-native cysteine residuessubstituting one or more amino acids of wild-type hNGAL. In a furtherparticular embodiment, an hNGAL mutein according to the disclosureincludes at least two amino acid substitutions of a native amino acid bya cysteine residue, hereby to form one or more cysteine bridges. In someembodiments, said cysteine bridge may connect at least two loop regions.The definition of these regions is used herein in accordance with Flower(Flower, 1996, supra, Flower, et al., 2000, supra) and Breustedt et al.(2005, supra).

A mutein or a composition thereof has specificity for CGRP as disclosedherein may have antagonist, or neutralizing or blocking activity withrespect to at least one biological activity of CGRP.

In one aspect, the present disclosure includes various hNGAL muteinsthat bind CGRP with at least detectable affinity. In this sense, CGRP isregarded as a non-natural ligand of the reference wild-type hNGAL, where“non-natural ligand” refers to a compound that does not bind towild-type human lipocalin 2 under physiological conditions. Byengineering wild-type hNGAL with one or more mutations at certainsequence positions, the present inventors have demonstrated that highaffinity and high specificity for the non-natural ligand, CGRP, ispossible. In some embodiments, at 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12or even more nucleotide triplet(s) encoding certain sequence positionson wild-type I human lipocalin 2, a random mutagenesis may be carriedout through substitution at these positions by a subset of nucleotidetriplets.

Further, the muteins of the disclosure may have a mutated amino acidresidue at any one or more, including at least at any one, two, three,four, five, six, seven, eight, nine, ten, eleven or twelve, of thesequence positions corresponding to certain sequence positions of thelinear polypeptide sequence of hNGAL, such as sequence positions 8, 9,28, 36, 38, 40, 41, 42, 44, 46, 47, 49, 52, 54, 62, 65, 66, 68, 70, 71,72, 73, 75, 76, 77, 79, 80, 81, 83, 87, 96, 97, 98, 100, 103, 105, 106,108, 111, 112, 114, 123, 125, 126, 127, 129, 132, 134, 135, 136, 145,146, 175, 176, 177 and 178 of the linear polypeptide sequence of humanNGAL (SEQ ID NO: 1).

A mutein of the disclosure may include the wild type (natural) aminoacid sequence of the “parental” protein scaffold (such as hNGAL) outsidethe mutated amino acid sequence positions. In some embodiments, an hNGALmutein according to the disclosure may also carry one or more amino acidmutations at a sequence position/positions as long as such a mutationdoes, at least essentially not hamper or not interfere with the bindingactivity and the folding of the mutein. Such mutations can beaccomplished very easily on DNA level using established standard methods(Sambrook, J. et al. (2001) Molecular Cloning: A Laboratory Manual, 3rdEd., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.).Illustrative examples of alterations of the amino acid sequence areinsertions or deletions as well as amino acid substitutions. Suchsubstitutions may be conservative, i.e. an amino acid residue isreplaced with an amino acid residue of chemically similar properties, inparticular with regard to polarity as well as size. Examples ofconservative substitutions are the replacements among the members of thefollowing groups: 1) alanine, serine, and threonine: 2) aspartic acidand glutamic acid; 3) asparagine and glutamine; 4) arginine and lysine;5) isoleucine, leucine, methionine, and valine; and 6) phenylalanine,tyrosine, and tryptophan. On the other hand, it is also possible tointroduce non-conservative alterations in the amino acid sequence. Inaddition, instead of replacing single amino acid residues, it is alsopossible to either insert or delete one or more continuous amino acidsof the primary structure of the human lipocalin 2 as long as thesedeletions or insertion result in a stable folded/functional mutein (forexample, hNGAL muteins with truncated N- and C-terminus). In suchmutein, for instance, one or more amino acid residues are added ordeleted at the N- or C-terminus of the polypeptide. Generally such amutein may have about at least 70%, including at least about 80%, suchas at least about 85% amino acid sequence identity, with the amino acidsequence of the mature hNGAL.

The amino acid sequence of an hNGAL mutein disclosed herein has a highsequence identity to the mature hNGAL (SEQ ID NO: 1) when compared tosequence identities with other lipocalins. In this general context, theamino acid sequence of a mutein of the disclosure is at leastsubstantially similar to the amino acid sequence of the naturalwild-type hNGAL, with the proviso that possibly there are gaps (asdefined below) in an alignment that are the result of additions ordeletions of amino acids. A respective sequence of a mutein of thedisclosure, being substantially similar to the sequences of the maturehNGAL, has, in some embodiments, at least 70% identity or sequencehomology, at least 75% identity or sequence homology, at least 80%identity or sequence homology, at least 82% identity or sequencehomology, at least 85% identity or sequence homology, at least 87%identity or sequence homology, or at least 90% identity or sequencehomology including at least 95% identity or sequence homology, to thesequence of the mature hNGAL, with the proviso that the altered positionor sequence is retained and that one or more gaps are possible.

As used herein, a mutein of the disclosure “specifically binds” a target(for example, CGRP) if it is able to discriminate between that targetand one or more reference targets, since binding specificity is not anabsolute, but a relative property. “Specific binding” can be determined,for example, in accordance with Western blots, ELISA-, RIA-, ECL-,IRMA-tests, FACS, IHC and peptide scans.

In one embodiment, the muteins of the disclosure are fused at itsN-terminus and/or its C-terminus to a fusion partner, which, in someparticular embodiments, is a protein, or a protein domain or a peptide.In some embodiments, the protein domain may extend the serum half-lifeof the mutein. In further particular embodiments, the protein domain isan Fc part of an immunoglobulin, a CH3 domain of an immunoglobulin, aCH4 domain of an immunoglobulin, an albumin binding peptide, or analbumin binding protein.

In another embodiment, the muteins of the disclosure are conjugated to acompound that extends the serum half-life of the mutein. Morepreferably, the mutein is conjugated to a compound selected from thegroup consisting of a polyalkylene glycol molecule, a hydroethylstarch,an Fc part of an immunoglobulin, a CH3 domain of an immoglobulin, a CH4domain of an immunoglobulin, an albumin binding peptide, and an albuminbinding protein.

In yet another embodiment, the current disclosure relates to a nucleicacid molecule comprising a nucleotide sequence encoding a muteindisclosed herein.

In another embodiment, the current disclosure relates to an expressionvector comprising said nucleic acid molecule.

In another embodiment, the disclosure encompasses a host cell or atransformed cell comprising said nucleic acid molecule.

In another embodiment, the disclosure encompasses a method for producinga mutein disclosed herein using a host cell or a transformed cellcomprising said nucleic acid molecule.

In another embodiment, the disclosure encompasses a pharmaceuticalcomposition comprising a mutein disclosed herein as an activeingredient.

A. Exemplary Muteins Specific for CGRP

In one aspect, the present disclosure relates to a novel,specific-binding human lipocalin 2 (human Lcn2 or hNGAL) mutein specificfor CGRP.

One embodiment of the current disclosure relates to an hNGAL mutein thatis capable of binding at least one of human α-CGRP (SEQ ID NO: 80) andhuman β-CGRP (SEQ ID NO: 81) with detectable affinity, such as anaffinity measured by a KD of about 200 nM or lower, such as about 150 nMor lower, for example, when measured in a competition ELISA assayessentially described in Example 4.

In one aspect, the current disclosure provides an hNGAL mutein that maybe further capable of binding CGRP with a K_(D) of about 5 nM or lower,such as about 2 nM or lower, for example, when measured by Biacore T200instrument in a SPR based assay essentially described in Example 5.

In some other embodiments, an hNGAL mutein of this disclosure may befurther capable of inhibiting or reducing CGRP induced cAMP productionwith an IC50 value of about 5 nM or lower, such as about 1.7 nM orlower, in a SK-N-MC cell-based functional assay essentially described inExample 6.

In some particular embodiments, an hNGAL mutein of the disclosure may befurther capable binding at least one of rat α-CGRP (SEQ ID NO: 82) andrat β-CGRP (SEQ ID NO: 83) with detectable affinity, such as an affinitymeasured by a K_(D) of about 200 nM or lower, such as about 150 nM orlower, for example, when measured in a competition ELISA assayessentially described in Example 4.

In another aspect, the current disclosure provides an hNGAL mutein thatmay be further capable of binding rat CGRP with a K_(D) of about 5 nM orlower, for example, when measured by a SPR based assay essentiallydescribed in Example 5.

In some still further embodiments, an hNGAL mutein of the disclosure maybe further capable of inhibiting or reducing rat CGRP induced cAMPproduction with an IC50 value of about 5 nM or lower, such as about 0.2nM or lower, in a L6 cell-based functional assay essentially describedin Example 6.

In some embodiments, an hNGAL mutein of this disclosure may be furthercrossreactive with both human CGRP and rat CGRP.

In some other embodiments, an hNGAL mutein of this disclosure may befurther crossreactive with both human α-CGRP and human β-CGRP.

In some other embodiments, an hNGAL mutein of this disclosure may befurther crossreactive with both rat α-CGRP and rat β-CGRP.

In this regard, the disclosure relates to one or more hNGAL muteins,wherein said hNGAL muteins in comparison with the linear polypeptidesequence of the mature hNGAL, may further comprise at least 1, 2, 3, 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or evenmore, a mutated amino acid residue at one or more positionscorresponding to the sequence positions 8, 9, 28, 36, 38, 40, 41, 42,44, 46, 47, 49, 52, 54, 62, 65, 66, 68, 70, 71, 72, 73, 75, 76, 77, 79,80, 81, 83, 87, 96, 97, 98, 100, 103, 105, 106, 108, 111, 112, 114, 123,125, 126, 127, 129, 132, 134, 135, 136, 145, 146, 175, 176, 177 and 178of the linear polypeptide sequence of the mature hNGAL (SEQ ID NO: 1),and wherein said hNGAL muteins bind CGRP with detectable affinity.

In some embodiments, an hNGAL mutein of the disclosure may furthercomprise a mutated amino acid residue at any one or more positionscorresponding to the sequence positions 36, 40, 41, 49, 52, 68, 70, 72,73, 77, 79, 81, 96, 100, 103, 106, 125, 127, 132 and 134 of the linearpolypeptide sequence of the mature hNGAL (SEQ ID NO: 1).

In some embodiments, an hNGAL mutein of the disclosure may furthercomprise at least one of the following mutated amino acid residue incomparison with the linear polypeptide sequence of the mature hNGAL: Leu36→Ile, Phe, Trp, Arg or Glu; Ala 40→Met, Trp or Thr; Ile 41→Leu, Trp,Gly or Glu; Gln 49→Leu, Phe, Lys, Glu or Thr; Tyr 52→Ala, Gly, Glu orGln; Ser 68→Trp, His or Asp; Leu 70→Met, Trp, Tyr, Gly or Gln; Arg72→Met, Ile, Trp, Glu or Ser; Lys 73→Ala, Glu, Thr or Gln; Asp 77→Ile orAsn; Trp 79→Val, Gly, His or Thr; Arg 81→Gly, His, Glu or Asn; Asn96→Ala, Gly or Thr; Tyr 100→Ile, Pro or Glu; Leu 103→Met, Glu, Thr orGln; Tyr 106→Leu, Ile, Ala, His or Asn; Lys 125 Val, Phe, Gly or Glu;Ser 127→Phe, Trp or Arg; Tyr 132→Leu, Ile or Trp; Lys 134→Trp, His orGlu.

In some embodiments, an hNGAL mutein of the disclosure may furthercomprise two or more, such as 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,15, 16, or even more or all mutated amino acid residues at thesesequence positions of the mature hNGAL.

Additionally, an hNGAL mutein according to the disclosure may alsocomprise the following substitution in comparison with the linearpolypeptide sequence of the mature hNGAL: Gln 28→His and Cys 87→Ser.

In some additional embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions in comparison with the linear polypeptide sequence ofthe mature hNGAL:

-   -   (a) Gln 28→His; Leu 36→Glu; Ala 40→Trp; Ile 41→Gly; Gln 49→Lys;        Tyr 52→Ala; Ser 68→Asp; Leu 70→Gln; Arg 72→Ile; Lys 73→Glu; Arg        81→Gly; Cys 87→Ser; Asn 96→Ala; Tyr 100→Glu; Leu 103→Gln; Tyr        106→Asn; Lys 125→Glu; Ser 127→Trp; Tyr 132→Leu; Lys 134→Trp;    -   (b) Gln 28→His; Leu 36→Phe; Ala 40→Met; Ile 41→Trp; Gln 49→Phe;        Tyr 52→Gly; Ser 68→Trp; Leu 70→Trp; Arg 72→Glu; Lys 73→Ala; Trp        79→Gly; Arg 81→Asn; Cys 87→Ser; Asn 96→Gly; Tyr 100→Pro; Leu        103→Met; Tyr 106→His; Lys 125→Glu; Ser 127→Phe; Tyr 132→Trp; Lys        134→Trp;    -   (c) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Thr;        Tyr 52→Gln; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys 73→Glu; Asp        77→) Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu        103→Glu; Tyr 106→Ile; Lys 125→Gly; Tyr 132→Ile; Lys 134→Glu;    -   (d) Gln 28→His; Leu 36→Arg; Ile 41→Glu; Gln 49→Glu; Tyr 52→Glu;        Ser 68→Asp; Leu 70→Gly; Arg 72→Trp; Lys 73→Gln; Asp 77→Ile; Trp        79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Thr; Tyr 106→Ala; Lys        125→Val; Ser 127→Arg; Tyr 132→Trp; Lys 134→Glu; or    -   (e) Gln 28→His; Leu 36→Ile; Ala 40→Trp; Ile 41→Trp; Gln 49→Leu;        Ser 68→His; Leu 70→Met; Arg 72→Met; Lys 73→Thr; Trp 79→Thr; Cys        87→Ser; Tyr 100→Ile; Leu 103→Met; Tyr 106→Leu; Lys 125→Phe; Ser        127→Trp; Tyr 132→Trp; Lys 134→His.

Moreover, an hNGAL mutein according to the disclosure may furthercomprise the following substitution in comparison with the linearpolypeptide sequence of the mature hNGAL: Gln 28→His; Leu 36→Trp; Ala40→Thr; Ile 41→Leu; Leu 42→Arg; Asp 47→Asn; Gln 49→Ile, Pro or Thr; Tyr52-4 Gln; Thr 54→Met, Ile or Lys; Lys 62→Arg; Asn 65→Asp; Val 66→Ala;Ser 68→Trp; Leu 70→Tyr; Phe 71→Leu; Arg 72→Ala or Ser; Lys 73→Asp orGlu; Lys 75→Arg; Asp 77→Arg or Asn; Trp 79→His; Arg 81→Glu; Phe 83→Ser;Cys 87→Ser; Asn 96→Leu or Thr; Ile 97→Thr; Lys 98-4 Gln; Tyr 100→His;Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Val 111→Met; Lys 125→Gly; Val126→Met; Ser 127→Gly or Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile orVal; Thr 145→Ala and Ser 146→Asn.

In some particular embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions in comparison with the linear polypeptide sequence ofthe mature hNGAL:

-   -   (a) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys 73→Glu; Lys        75→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe 83→Ser; Cys        87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys 125→Gly; Tyr        132→Ile; Lys 134→Glu;    -   (b) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Leu 42→Arg;        Asp 47→Asn; Gln 49→Thr; Tyr 52→Gln; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe        83→Ser; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys        125→Gly; Tyr 132→Ile; Lys 134→Glu;    -   (c) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Asn 65→Asp; Ser 68→Trp; Leu 70→Tyr; Phe 71→Leu; Arg        72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe        83→Ser; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys        125→Gly; Val 126→Met; Tyr 132→Ile; Lys 134→Glu; Thr 145→Ala;    -   (d) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Asp 47→Asn;        Gln 49→Thr; Tyr 52→Gln; Val 66→Ala; Ser 68→Trp; Leu 70→Tyr; Phe        71→Leu; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg        81→Glu; Phe 83→Ser; Cys 87→Ser; Asn 96→Thr; Ile 97→Thr; Leu        103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Tyr 132→Ile; Lys        134→Glu;    -   (e) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Ile; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys        87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys        125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser        146→Asn;    -   (f) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Pro;        Tyr 52→Gln; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys        73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe 83→Ser; Cys        87→Ser; Asn 96→Thr; Lys 98→Gln; Tyr 100→His; Leu 103→Glu; Ser        105→Pro; Tyr 106→Ile; Lys 125→Gly; Val 126→Met; Ser 127→Gly; Tyr        132→Ile; Lys 134→Glu;    -   (g) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ala; Lys 73→Asp; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys        87→Ser; Asn 96→Leu; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys        125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser        146→Asn;    -   (h) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41-3 Leu; Gln        49→Ile; Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu        70→Tyr; Arg 72→Ala; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg        81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr        106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr        136→Ile; Ser 146→Asn;    -   (i) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ala; Lys 73→Asp; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys        87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys        125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser        146→Asn;    -   (j) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ala; Lys 73→Asp; Asp 77→Arg; Trp 79→His; Arg 81→Glu; Cys        87→Ser; Asn 96→Thr; Tyr 100→His; Leu 103→Glu; Ser 105→Pro; Tyr        106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr        136→Ile; Ser 146→Asn;    -   (k) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys        73→Asp; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; or    -   (l) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;        Tyr 52→Gln; Thr 54→Ile; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg        72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys        87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Val        111→Met; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr        136→Ile; Ser 146→Asn.

Additionally, an hNGAL mutein according to the disclosure may alsocomprise the following substitution in comparison with the linearpolypeptide sequence of the mature hNGAL: Cys 76→Leu, Met, Val, Ile,Phe, Arg, Lys or Asn and Cys 175→Leu, Val, Phe, Trp, Tyr, Asp or Glu.

In some particular embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions in comparison with the linear polypeptide sequence ofthe mature hNGAL:

-   -   (a) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Phe;    -   (b) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Met; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Tyr;    -   (c) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Leu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Trp;    -   (d) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Ile; Asp 77→Asn; Trp 79→His; Arg 81→→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Glu;    -   (e) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Val; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Tyr;    -   (f) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Trp;    -   (g) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Asn; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Leu;    -   (h) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Val;    -   (i) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Lys; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Asp; or    -   (j) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Phe; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Asp.

In addition, an hNGAL mutein according to the disclosure may furthercomprise the following substitution in comparison with the linearpolypeptide sequence of the mature hNGAL: Gln 28→His; Leu 36→Arg; Gly38→Ala; Ala 40→Asp or Glu; Ile 41→Val, Thr, Ala, Arg or Glu; Glu 44→Lysor Asp; Lys 46→Asn; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe71→Leu; Arg 72→Val or Ser; Lys 73→Arg, Glu or Gln; Lys 75→Arg; Asp77→Met or Ile; Trp 79→Val; Ile 80→Val or Thr; Arg 81→His; Cys 87→Ser orGly; Lys 98→Glu; Leu 103→Val or Thr; Tyr 106→Ala or Gly; Val 108→Ile;Ser 112→Asn; Asn 114→Asp; Phe 123→Val; Lys 125→Leu or Val; Ser 127→Gly,Arg or Lys; Asn 129→Ser; Tyr 132→Leu or Ser; Lys 134→Glu and Ile135→Val.

In some particular embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions in comparison with the linear polypeptide sequence ofthe mature hNGAL:

-   -   (a) Gln 28→His; Leu 36→Arg; Ala 40→Glu; Ile 41→Glu; Tyr 52→Glu;        Ser 68→Asp; Leu 70→Gly; Arg 72→Ser; Lys 73→Glu; Asp 77→Ile; Trp        79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr 106→Ala; Lys        125→Val; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu;    -   (b) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Ala; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Asp        77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr        106→Ala; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu;    -   (c) Gln 28→His; Leu 36→Arg; Gly 38→Ala; Ala 40→Asp; Ile 41→Arg;        Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Ser; Lys        73→Arg; Asp 77→Ile; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu        103→Thr; Tyr 106→Gly; Lys 125→Val; Ser 127→Gly; Tyr 132→Ser; Lys        134→Glu;    -   (d) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Glu; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Asp        77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr        106→Gly; Lys 125→Val; Ser 127→Arg; Tyr 132→Leu; Lys 134→Glu;    -   (e) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys        75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys        87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe        123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu;    -   (f) Gln 28→His; Leu 36→Arg; Gly 38→Ala; Ala 40→Asp; Ile 41→Val;        Glu 44→Asp; Lys 46→Asn; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu        70→Gly; Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Ile        80→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr 106→Ala; Lys        125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Ile 135→Val;    -   (g) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Thr; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe 71→Leu; Arg 72→Val; Lys        73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu        103→Val; Tyr 106→Ala; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Asn        129→Ser; Tyr 132→Leu; Lys 134→Glu;    -   (h) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Thr; Glu 44→Lys;        Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys        73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu        103→Val; Tyr 106→Ala; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr        132→Leu; Lys 134→Glu;    -   (i) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Ala; Gln 49→Glu;        Tyr 52 Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Asp        77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr        106→Ala; Val 108→lie; Ser 112→Asn; Phe 123→Val; Lys 125→Leu; Ser        127→Lys; Tyr 132→Leu; Lys 134→Glu; or    -   (j) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Ala; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe 71→Leu; Arg 72→Val; Lys        73-4 Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys 87→Gly; Leu        103→Val; Tyr 106→Ala; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr        132→Leu; Lys 134→Glu.

Additionally, an hNGAL mutein according to the disclosure may alsocomprise the following substitution in comparison with the linearpolypeptide sequence of the mature hNGAL: Cys 76→Leu or Tyr; Cys175→Ile; Ile 176→Asp and Asp 177→Gly.

In some particular embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions in comparison with the linear polypeptide sequence ofthe mature hNGAL:

-   -   (a) Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu;        Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Cys        76→Leu; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His: Cys        87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→k Asp; Phe        123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Cys        175→Ile; Ile 176→Asp; Asp 177→Gly; or    -   (b) Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu;        Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Cys        76→Tyr; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys        87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe        123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Cys        175→Ile; Ile 176→Asp; Asp 177→Gly.

In addition, an hNGAL mutein according to the disclosure may furthercomprise the following substitution and addition in comparison with thelinear polypeptide sequence of the mature hNGAL: Ile 8→Lys; Pro 9→His;Gln 28→His; Leu 36→Trp or Arg; Ala 40→Thr or Asp; Ile 41→Leu or Val; Gln49→Ile or Glu; Tyr 52→Gln or Glu; Thr 54→Met; Asn 65→Gln; Ser 68→Trp orAsp; Leu 70→Tyr or Gly; Arg 72→Ala or Val; Lys 73→Asp or Gln; Lys75→Arg; Cys 76→Ile; Asp 77→Asn or Met; Trp 79→His or Val; Ile 80→Thr;Arg 81→Glu or His; Cys 87→Ser; Asn 96→Thr; Lys 98→Glu; Leu 103→Glu orVal; Ser 105→Pro; Tyr 106→Ile or Ala; Asn 114→Asp; Phe 123→Val; Lys125→Gly or Leu; Ser 127→Asn or Lys; Tyr 132→Ile or Leu; Lys 134→Glu; Thr136→Val; Ser 146→Asn; Cys 175→Glu; Gly 178→Asp and Gly is added toN-terminal amino acid (Gln 1).

In some particular embodiments, an hNGAL mutein of the disclosure, whichbinds to CGRP, may further comprise one of the following sets of aminoacid substitutions and additions in comparison with the linearpolypeptide sequence of the mature hNGAL:

-   -   (a) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;        Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys        76→Ile; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn        96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser        127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys        175→Glu and Gly is added to N-terminal amino acid (Gln 1) (SEQ        ID NO: 87);    -   (b) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu;        Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys        75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys        87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe        123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu and        Gly is added to N-terminal amino acid (Gln 1) (SEQ ID NO: 88);    -   (c) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu;        Tyr 52→Glu; Asn 65→Gln; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys        73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg        81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn        114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys        134→Glu; Gly 178→Asp and Gly is added to N-terminal amino acid        (Gln 1) (SEQ ID NO: 89);    -   (d) Ile 8→Lys; Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val;        Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys        73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg        81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn        114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys        134→Glu and Gly is added to N-terminal amino acid (Gln 1) (SEQ        ID NO: 90);    -   (e) Pro 9→His: Gln 28→His, Leu 36→Arg; Ala 40→Asp; Ile 41→Val;        Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys        73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg        81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn        114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys        134→Glu and Gly is added to N-terminal amino acid (Gln 1) (SEQ        ID NO: 91);    -   (f) Ile 8→Lys; Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val;        Gln 49→Glu; Tyr 52→Glu; Asn 65→Gln; Ser 68→Asp; Leu 70→Gly; Arg        72→Val; Lys 73 Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile        80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr        106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr        132→Leu; Lys 134→Glu; Gly 178→Asp and Gly is added to N-terminal        amino acid (Gln 1) (SEQ ID NO: 92); or    -   (g) Pro 9→His; Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val;        Gln 49→Glu; Tyr 52→Glu; Asn 65→Gln; Ser 68→Asp; Leu 70→Gly; Arg        72→Val; Lys 73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile        80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr        106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr        132→Leu; Lys 134→Glu; Gly 178→Asp and Gly is added to N-terminal        amino acid (Gln 1) (SEQ ID NO: 93).

In the residual region, i.e. the region differing from sequencepositions 8, 9, 28, 36, 38, 40, 41, 42, 44, 46, 47, 49, 52, 54, 62, 65,66, 68, 70, 71, 72, 73, 75, 76, 77, 79, 80, 81, 83, 87, 96, 97, 98, 100,103, 105, 106, 108, 111, 112, 114, 123, 125, 126, 127, 129, 132, 134,135, 136, 145, 146, 175, 176, 177 and 178, an hNGAL mutein of thedisclosure may include the wild type (natural) amino acid sequenceoutside the mutated amino acid sequence positions.

In further particular embodiments, a mutein according to the currentdisclosure comprises an amino acid sequence selected from the groupconsisting of SEQ ID NOs: 2-40, 87-93 or a functional fragment orvariant thereof. In some embodiments, such fragment or variant is astructural homologue of a mutein defined in any one of SEQ ID NOs: 2-40,87-93.

The amino acid sequence of an hNGAL mutein of the disclosure may have ahigh sequence identity, such as at least 70%, at least 75%, at least80%, at least 82%, at least 85%, at least 87%, at least 90% identity,including at least 95% identity, to a sequence selected from the groupconsisting of SEQ ID NOs: 2-40, 87-93.

In some still embodiments, an hNGAL mutein is crossreactive with orbinding to human CGRP and/or rat CGRP according to the disclosurecomprises an amino acid sequence selected from the group consisting ofSEQ ID NOs: 2-40, 87-93 and functional fragments or variants thereof.

The disclosure also includes structural homologues of an hNGAL muteincomprising an amino acid sequence selected from the group consisting ofSEQ ID NOs: 2-40, 87-93, which structural homologues have an amino acidsequence homology or sequence identity of more than about 60%,preferably more than 65%, more than 70%, more than 75%, more than 80%,more than 85%, more than 90%, more than 92% and most preferably morethan 95% in relation to said hNGAL mutein and bind to CGRP.

An hNGAL mutein according to the present disclosure can be obtained bymeans of mutagenesis of a naturally occurring form of human lipocalin 2.In some embodiments of the mutagenesis, a substitution (or replacement)is a conservative substitution. Nevertheless, any substitution—includingnon-conservative substitution or one or more from the exemplarysubstitutions below—is envisaged as long as the mutein retains itscapability to bind to CGRP, and/or it has an identity to the thensubstituted sequence in that it is at least 60%, such as at least 65%,at least 70%, at least 75%, at least 80%, at least 85% or higheridentity to the amino acid sequence of the mature human lipocalin 2(SWISS-PROT Data Bank Accession Number P80188, SEQ ID NO: 1).

The present disclosure also relates to a pharmaceutical composition thatincludes at least one hNGAL mutein disclosed herein, or conjugate orfusion protein thereof as described herein, and a pharmaceuticallyacceptable excipient.

Accordingly, the hNGAL muteins of the disclosure can be formulated intocompositions using pharmaceutically acceptable ingredients as well asestablished methods of preparation (Gennaro and Gennaro (2000)Remington: The Science and Practice of Pharmacy, 20th Ed., LippincottWilliams & Wilkins, Philadelphia, Pa.). To prepare the pharmaceuticalcompositions, pharmaceutically inert inorganic or organic excipients canbe used.

B. Applications of Muteins Specific for CGRP

Recently, Arulmozhi and colleagues have reported, various theories onmigraines (Vascular Pharmacology 43; 176-187, 2005). One of the theoriesproposes that the currently unknown triggers of migraine stimulatetrigeminal nerves and ganglia that innervate cephalic tissue, givingrise to release of neuropeptide messenger molecules from axons on thevasculature. Release of these neuropeptides then activates a series ofevents, a consequence of which is migraine pain. In addition, release ofthese neuropeptides changes vascular permeability resulting insubsequent leakage of plasma proteins in tissues innervated bystimulated trigeminal fibers. This leakage results in neurogenicinflammation which leads to migraines.

Of these neuropeptides, CGRP has been reported to play a role inmigraines as CGRP is released upon stimulation of sensory nerves and haspotent vasodilatory activity. (Vascular Pharmacology 43; 176-187, 2005).Further, the release of CGRP increases vascular permeability andsubsequent plasma protein leakage (plasma protein extravasation) intissues innervated by trigeminal nerve fibers upon stimulation of thesefibers. (Vascular Pharmacology 43; 176-187, 2005). In addition, studieshave reported that infusion of CGRP in patients who suffer frommigraines has resulted in migraine-like symptoms. (Cephalagia 22(1):54-61, 2002).

Historically, small molecule agonists of serotonin 5-HT1B and 5-HT1Dreceptors have been used as treatments for migraines. These so-calledtriptans are potent vasoconstrictors and have been shown to inhibitplasma protein extravasation due to stimulation of trigeminal nervefibers in an experimental animal migraine model. In addition, doses of atriptan that decreased plasma protein extravasation also attenuated CGRPlevels in the same experimental animal model. (Br. J. Pharmacology 99;202-206, 1990; Neuropharmacology 30(11): 1193-1200, 1991).

Although triptans have been found to be efficacious, many patients whorespond to triptan treatment suffer from recurrent headaches withinseveral hours after treatment. Further, since triptans are potentvasoconstrictors, they are contraindicated in certain patientpopulations, such as populations of patients suffering from hypertensionor suffering from ischemic heart disease. There is therefore a need fortherapeutic compounds to prevent and/or treat migraines without unwantedside effects such as cardiovascular-related effects.

Numerous possible applications for the muteins with binding-affinity forCGRP of the disclosure, therefore, exist in medicine, for example, inmigraine, temporomandibular joint disorder as well as a variety of otherdiseases such as cardiac failure, hypertension, and sepsis. In onefurther aspect, the disclosure relates to the use of such a muteindisclosed herein for detecting CGRP in a sample as well as a respectivemethod of diagnosis.

The present disclosure also involves the use of one or more muteins withbinding-affinity for CGRP as described for complex formation with CGRP.

Therefore, in another aspect of the disclosure, the disclosed muteinsare used for the detection of CGRP. Such use may include the steps ofcontacting one or more said muteins, under suitable conditions, with asample suspected of containing CGRP, thereby allowing formation of acomplex between the muteins and CGRP, and detecting the complex by asuitable signal.

The detectable signal can be caused by a label, as explained above, orby a change of physical properties due to the binding, i.e. the complexformation, itself. One example is SPR, the value of which is changedduring binding of binding partners from which one is immobilized on asurface such as a gold foil.

The muteins disclosed herein may also be used for the separation of CGR.Such use may include the steps of contacting one or more said muteins,under suitable conditions, with a sample supposed to contain CGRP,thereby allowing formation of a complex between the muteins and CGRP,and separating the complex from the sample.

In the use of the disclosed muteins for the detection of CGRP as well asthe separation of CGRP, the muteins and/or CGRP or a domain or fragmentthereof may be immobilized on a suitable solid phase.

Accordingly, the presence or absence of a molecule such as CGRP, e.g.,in a sample, as well as its concentration or level may be determined.

The muteins of the present disclosure, therefore, may be used to detectand/or measure CGRP in a sample, e.g., for diagnostic purposes. Forexample, the muteins may be used to diagnose a condition or diseasecharacterized by aberrant expression (e.g., over-expression,under-expression, lack of expression, etc.) of CGRP. Exemplarydiagnostic assays for CGRP may comprise, e.g., contacting a sample,obtained from a patient, with the muteins, wherein the muteins arelabeled with a detectable label or reporter molecule. Alternatively,unlabeled the muteins can be used in diagnostic applications incombination with a secondary molecule which is itself detectablylabeled. The detectable label or reporter molecule can be aradioisotope, such as ³H, ¹⁴C, ³²P, ³⁵S, or ¹²⁵I; a fluorescent orchemiluminescent moiety such as fluorescein isothiocyanate, orrhodamine; or an enzyme such as alkaline phosphatase, β-galactosidase,horseradish peroxidase, or luciferase. Specific exemplary assays thatcan be used to detect or measure CGRP in a sample include enzyme-linkedimmunosorbent assay (ELISA), radioimmunoassay (RIA), andfluorescence-activated cell sorting (FACS).

In still another aspect, the present disclosure features a diagnostic oranalytical kit comprising a mutein with binding-affinity for CGRPaccording to the disclosure.

In a further aspect, the disclosure also encompasses the use ofdisclosed hNGAL muteins or combinations comprising such muteinsdescribed herein for the manufacture of a pharmaceutical composition.The pharmaceutical composition thus obtained may be suited to decreasecirculating levels of free CGRP which is useful for the treatment orprevention of migraines in subjects, preferably humans. Thepharmaceutical composition may be used as monotherapy or as combinationtherapy. Accordingly, the disclosure also provides hNGAL muteins for thetreatment of a disease or disorder associated with deregulated proteinplasma extravasation.

In addition to their use in diagnostics, in yet another aspect, thedisclosure encompasses the use of such a mutein of the disclosure or acomposition or a combination comprising such mutein for the binding ofCGRP in a subject and/or reducing the amount of protein extravasation ina subject. In some embodiments, such subject may suffer from diseases ordisorders caused by a release of neuropeptides, which changes vascularpermeability resulting in subsequent leakage of plasma proteins intissues innervated by stimulated trigeminal fibers.

In still another aspect, the present disclosure features a method ofbinding CGRP in a subject, comprising administering to said subject aneffective amount of one or more muteins with binding-affinity for CGRPof the disclosure or of one or more compositions or combinationscomprising such the mutein.

In still another aspect, the present disclosure involves a method forinhibiting or reducing migraines in a subject, comprising administeringto said subject an effective amount of one or more muteins of thedisclosure with binding-affinity for CGRP or fragments of CGRP or of oneor more compositions or combinations comprising such muteins. In someembodiments, such subject may suffer from diseases or disordersassociated with deregulated levels of free CGRP.

The muteins of the disclosure or compositions or combinations comprisingsuch muteins are useful, inter alia, for the treatment, preventionand/or amelioration of any disease or disorder associated with CGRPactivity, including diseases or disorders associated with deregulatedlevels of free CGRP.

In still another aspect, the present disclosure involves a method forinhibiting or reducing plasma protein extravasation in a subject,comprising administering to said subject an effective amount of one ormore muteins of the disclosure with binding-affinity for CGRP orfragments of CGRP or of one or more compositions or combinationscomprising such muteins.

For example, the muteins or compositions or combinations comprising suchmuteins of the disclosure may be used to decrease circulating levels offree CGRP.

In some other embodiments, the muteins or compositions or combinationscomprising such muteins of the present disclosure may also be useful forthe treatment, prevention and/or amelioration of migraines.

The hNGAL muteins according to the disclosure or compositions orcombinations comprising such muteins can be administered via anyparenteral or non-parenteral (e.g. enteral) route that istherapeutically effective. A therapeutically effective route providesfor delivery of an agent to a desired compartment, system, or location.For example, a therapeutically effective route is one through which anagent can be administered to provide at the desired site of action anamount of the agent sufficient to effectuate a beneficial or desiredclinical result.

C. Muteins of the Disclosure

When used herein in the context of the muteins of the present disclosurethat bind to CGRP, the term “specific for” includes that the mutein isdirected against, binds to, or reacts with CGRP. Thus, being directedto, binding to or reacting with includes that the mutein specificallybinds to CGRP. The term “specifically” in this context means that themutein reacts with a CGRP, as described herein, but essentially not withanother target. Whether the mutein specifically reacts as defined hereinabove can easily be tested, inter alia, by comparing the reaction of ahNGAL mutein of the present disclosure with CGRP and the reaction ofsaid mutein with (an) other target(s). “Specific binding” can also bedetermined, for example, in accordance with Western blots, ELISA-, RIA-,ECL-, IRMA-tests, FACS, IHC and peptide scans.

The amino acid sequence of a mutein according to the disclosure has ahigh sequence identity to human lipocalin 2 when compared to sequenceidentities with another lipocalin (see also above). In this generalcontext the amino acid sequence of a mutein of the combination accordingto the disclosure is at least substantially similar to the amino acidsequence of the corresponding lipocalin (the wild-type hNGAL). Arespective sequence of a mutein of the combination according to thedisclosure, being substantially similar to the sequence of mature hNGAL,such as at least 65%, at least 70%, at least 75%, at least 80%, at least82%, at least 85%, at least 87%, at least 90% identity, including atleast 95% identity to the sequence of mature hNGAL. In this regard, amutein of the disclosure of course may contain, in comparisonsubstitutions as described herein which renders the mutein capable ofbinding to CGRP. Typically a mutein of hNGAL includes one or moremutations—relative to the native sequence of hNGAL—of amino acids in thefour loops at the open end of the ligand binding site of hNGAL. Asexplained above, these regions are essential in determining the bindingspecificity of a mutein for CGRP. A mutein derived hNGAL or a homologuethereof, may have one, two, three, four or more mutated amino acidresidues at any sequence position in the N-terminal region and/or in thethree peptide loops BC, DE, and FG arranged at the end of the β-barrelstructure that is located opposite to the natural binding pocket. Insome particular embodiments, an hNGAL mutein according to the presentdisclosure comprises four loops of one of SEQ ID NOs: 2-40, 87-93 whichtogether define a binding pocket for CGRP.

A mutein according to the disclosure includes one or more, such as two,three, four, five, six, seven, eight, nine, ten, eleven, twelve,thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen oreven twenty substitutions in comparison to the corresponding nativehNGAL, provided that such a mutein should be capable of binding to CGRP.For example, a mutein can have a substitution at a positioncorresponding to a distinct position (i.e. at a corresponding position)of hNGAL. In some embodiments a mutein of the combination according tothe disclosure includes at least two amino acid substitutions, including2, 3, 4, 5, or even more, amino acid substitutions of a native aminoacid by an arginine residue. Accordingly, the nucleic acid of a protein‘reference’ scaffold as described herein is subject to mutagenesis withthe aim of generating a mutein which is capable of binding to CGRP.

Also, a mutein of the present disclosure can comprise a heterologousamino acid sequence at its N- or C-terminus, preferably C-terminus, suchas a Strep-tag, e.g., Strep II tag without affecting the biologicalactivity (binding to its target e.g. CGRP) of the mutein.

Specifically, in order to determine whether an amino acid residue of theamino acid sequence of a mutein different from wild-type hNGALcorresponds to a certain position in the amino acid sequence ofwild-type hNGAL, a skilled artisan can use means and methods well-knownin the art, e.g., alignments, either manually or by using computerprograms such as BLAST2.0, which stands for Basic Local Alignment SearchTool or ClustalW or any other suitable program which is suitable togenerate sequence alignments. Accordingly, wild-type hNGAL can serve as“subject sequence” or “reference sequence”, while the amino acidsequence of a mutein different from the wild-type hNGAL described hereinserves as “query sequence”. The terms “reference sequence” and “wildtype sequence” are used interchangeably herein.

In some embodiments a substitution (or replacement) is a conservativesubstitution. Nevertheless, any substitution—including non-conservativesubstitution or one or more from the exemplary substitutions listedbelow—is envisaged as long as the mutein retains its capability to bindCGRP, and/or it has an identity to the then substituted sequence in thatit is at least 60%, such as at least 65%, at least 70%, at least 75%, atleast 80%, at least 85% or higher identical to the “original” sequence.

Conservative substitutions are generally the following substitutions,listed according to the amino acid to be mutated, each followed by oneor more replacement(s) that can be taken to be conservative: Ala→Gly,Ser, Val; Arg→Lys; Asn→Gln, His; Asp→Glu; Cys→Ser; Gln→Asn; Glu→Asp;Gly→Ala; His→Arg, Asn, Gln; Ile→Leu, Val; Leu→Ile, Val; Lys→Arg, Gln,Glu; Met→Leu, Tyr, Ile; Phe→Met, Leu, Tyr; Ser→Thr; Thr→Ser; Trp→Tyr;Tyr→Trp, Phe; Val→Ile, Leu. Other substitutions are also permissible andcan be determined empirically or in accord with other known conservativeor non-conservative substitutions. As a further orientation, thefollowing eight groups each contain amino acids that can typically betaken to define conservative substitutions for one another:

a. Alanine (Ala), Glycine (Gly);b. Aspartic acid (Asp), Glutamic acid (Glu);c. Asparagine (Asn), Glutamine (Gln);d. Arginine (Arg), Lysine (Lys);e. Isoleucine (Ile), Leucine (Leu), Methionine (Met), Valine (Val);f. Phenylalanine (Phe), Tyrosine (Tyr), Tryptophan (Trp);g. Serine (Ser), Threonine (Thr); andh. Cysteine (Cys), Methionine (Met)

If such substitutions result in a change in biological activity, thenmore substantial changes, such as the following, or as further describedbelow in reference to amino acid classes, may be introduced and theproducts screened for a desired characteristic. Examples of such moresubstantial changes are: Ala→Leu, Ile; Arg→Gln; Asn→Asp, Lys, Arg, His;Asp→Asn; Cys→Ala; Gln→Glu; Glu→Gln; His→Lys; Ile→Met, Ala, Phe; Leu→Ala,Met, Norleucine; Lys→Asn; Met→Phe; Phe→Val, Ile, Ala; Trp→Phe; Tyr→Thr,Ser; Val→Met, Phe, Ala.

Substantial modifications in the biological properties of hNGAL areaccomplished by selecting substitutions that differ significantly intheir effect on maintaining (a) the structure of the polypeptidebackbone in the area of the substitution, for example, as a sheet orhelical conformation, (b) the charge or hydrophobicity of the moleculeat the target site, or (c) the bulk of the side chain. Naturallyoccurring residues are divided into groups based on common side-chainproperties: (1) hydrophobic: norleucine, methionine, alanine, valine,leucine, iso-leucine; (2) neutral hydrophilic: cysteine, serine,threonine; (3) acidic: aspartic acid, glutamic acid; (4) basic:asparagine, glutamine, histidine, lysine, arginine; (5) residues thatinfluence chain orientation: glycine, proline; and (6) aromatic:tryptophan, tyrosine, phenylalanine.

Non-conservative substitutions will entail exchanging a member of one ofthese classes for another class. Any cysteine residue not involved inmaintaining the proper conformation of hNGAL also may be substituted,generally with serine, to improve the oxidative stability of themolecule and prevent aberrant crosslinking. Conversely, cysteine bond(s) may be added to improve its stability.

Any mutation, including an insertion as discussed above, can beaccomplished very easily on the nucleic acid, e.g. DNA level usingestablished standard methods. Illustrative examples of alterations ofthe amino acid sequence are insertions or deletions as well as aminoacid substitutions. Such substitutions may be conservative, i.e. anamino acid residue is replaced with an amino acid residue of chemicallysimilar properties, in particular with regard to polarity as well assize. Examples of conservative substitutions are the replacements amongthe members of the following groups: 1) alanine, serine, and threonine;2) aspartic acid and glutamic acid; 3) asparagine and glutamine; 4)arginine and lysine; 5) iso-leucine, leucine, methionine, and valine;and 6) phenylalanine, tyrosine, and tryptophan. On the other hand, it isalso possible to introduce non-conservative alterations in the aminoacid sequence. In addition, instead of replacing single amino acidresidues, it is also possible to either insert or delete one or morecontinuous amino acids of the primary structure of hNGAL as long asthese deletions or insertion result in a stable folded/functionalmutein.

Modifications of the amino acid sequence include directed mutagenesis ofsingle amino acid positions in order to simplify sub-cloning of themutated hNGAL gene or its parts by incorporating cleavage sites forcertain restriction enzymes. In addition, these mutations can also beincorporated to further improve the affinity of a mutein for a giventarget such as CGRP. Furthermore, mutations can be introduced in orderto modulate certain characteristics of the mutein such as to improvefolding stability, serum stability, protein resistance or watersolubility or to reduce aggregation tendency, if necessary. For example,naturally occurring cysteine residues may be mutated to other aminoacids to prevent disulphide bridge formation. It is also possible todeliberately mutate other amino acid sequence position to cysteine inorder to introduce new reactive groups, for example for the conjugationto other compounds, such as polyethylene glycol (PEG), hydroxyethylstarch (HES), biotin, peptides or proteins, or for the formation ofnon-naturally occurring disulphide linkages. The generated thiol moietymay be used to PEGylate or HESylate the mutein, for example, in order toincrease the serum half-life of a respective mutein.

It is also possible to mutate other amino acid sequence positions tocysteine in order to introduce new reactive groups, for example, for theconjugation to other compounds, such as polyethylene glycol (PEG),hydroxyethyl starch (HES), biotin, peptides or proteins, or for theformation of non-naturally occurring disulphide linkages.

In some embodiments, if one of the above moieties is conjugated to amutein of the disclosure, conjugation to an amino acid side chain can beadvantageous. Suitable amino acid side chains may occur naturally in theamino acid sequence of hNGAL or may be introduced by mutagenesis. Incase a suitable binding site is introduced via mutagenesis, onepossibility is the replacement of an amino acid at the appropriateposition by a cysteine residue.

With respect to a mutein of human lipocalin 2, exemplary possibilitiesof such a mutation to introduce a cysteine residue into the amino acidsequence of a lipocalin including human lipocalin 2 mutein to includethe introduction of a cysteine (Cys) residue at least at one of thesequence positions that correspond to sequence positions 14, 21, 60, 84,88, 116, 141, 145, 143, 146 or 158 of the wild type sequence of humanNGAL. In some embodiments where a human lipocalin 2 mutein of thedisclosure has a sequence in which, in comparison to the sequence of theSWISS-PROT/UniProt Data Bank Accession Number P80188, a cysteine hasbeen replaced by another amino acid residue, the corresponding cysteinemay be reintroduced into the sequence. As an illustrative example, acysteine residue at amino acid position 87 may be introduced in such acase by reverting to a cysteine as originally present in the sequence ofSWISS-PROT accession No. P80188 (SEQ ID NO: 1). The generated thiolmoiety at the side of any of the amino acid positions 14, 21, 60, 84,88, 116, 141, 145, 143, 146 and/or 158 may be used to PEGylate orHESylate the mutein, for example, in order to increase the serumhalf-life of a respective human lipocalin 2 mutein.

In another embodiment, in order to provide suitable amino acid sidechains for conjugating one of the above compounds to a mutein accordingto the present disclosure, artificial amino acids may be introduced bymutagenesis. Generally, such artificial amino acids are designed to bemore reactive and thus to facilitate the conjugation to the desiredcompound. One example of such an artificial amino acid that may beintroduced via an artificial tRNA is para-acetyl-phenylalanine.

In some embodiments, a mutein of the disclosure may be fused at itsN-terminus or its C-terminus to a protein, a protein domain or apeptide, for instance, a signal sequence and/or an affinity tag.

Affinity tags such as the Strep-Tag® or Strep-Tag® II (Schmidt, T. G. M.et al. (1996) J. Mol. Biol 255, 753-766), the myc-tag, the FLAG-tag, theHis₆-tag or the HA-tag or proteins such as glutathione-S-transferasealso allow easy detection and/or purification of recombinant proteinsare further examples of suitable fusion partners. Finally, proteins withchromogenic or fluorescent properties such as the green fluorescentprotein (GFP) or the yellow fluorescent protein (YFP) are suitablefusion partners for muteins of the disclosure as well.

In general, it is possible to label the muteins of the disclosure withany appropriate chemical substance or enzyme, which directly orindirectly generates a detectable compound or signal in a chemical,physical, optical, or enzymatic reaction. An example for a physicalreaction and at the same time optical reaction/marker is the emission offluorescence upon irradiation or the emission of X-rays when using aradioactive label. Alkaline phosphatase, horseradish peroxidase andβ-galactosidase are examples of enzyme labels (and at the same timeoptical labels) which catalyze the formation of chromogenic reactionproducts. In general, all labels commonly used for antibodies (exceptthose exclusively used with the sugar moiety in the Fc part ofimmunoglobulins) can also be used for conjugation to the muteins of thedisclosure. The muteins of the disclosure may also be conjugated withany suitable therapeutically active agent, e.g., for the targeteddelivery of such agents to a given cell, tissue or organ or for theselective targeting of cells, e.g., of tumor cells without affecting thesurrounding normal cells. Examples of such therapeutically active agentsinclude radionuclides, toxins, small organic molecules, and therapeuticpeptides (such as peptides acting as agonists/antagonists of a cellsurface receptor or peptides competing for a protein binding site on agiven cellular target). The muteins of the disclosure may, however, alsobe conjugated with therapeutically active nucleic acids such asantisense nucleic acid molecules, small interfering RNAs, micro RNAs orribozymes. Such conjugates can be produced by methods well known in theart.

As indicated above, a mutein of the disclosure may in some embodimentsbe conjugated to a moiety that extends the serum half-life of the mutein(in this regard see also PCT publication WO 2006/56464 where suchconjugation strategies are described with references to muteins of humanneutrophile gelatinase-associated lipocalin with binding affinity forCTLA-4). The moiety that extends the serum half-life may be apolyalkylene glycol molecule, hydroxyethyl starch, fatty acid molecules,such as palmitic acid (Vajo & Duckworth 2000, Pharmacol. Rev. 52, 1-9),an Fc part of an immunoglobulin, a CH3 domain of an immunoglobulin, aCH4 domain of an immunoglobulin, an albumin binding peptide, or analbumin binding protein, transferrin to name only a few. The albuminbinding protein may be a bacterial albumin binding protein, an antibody,an antibody fragment including domain antibodies (see U.S. Pat. No.6,696,245, for example), or a mutein with binding activity for albumin.Accordingly, suitable conjugation partners for extending the half-lifeof a mutein of the disclosure include an albumin binding protein, forexample, a bacterial albumin binding domain, such as the one ofstreptococcal protein G (König, T., & Skerra, A. (1998) J. Immunol.Methods 218, 73-83). Other examples of albumin binding peptides that canbe used as conjugation partner are, for instance, those comprising aCys-Xaa₁-Xaa₂-Xaa₃-Xaa₄-Cys consensus sequence, wherein Xaa₁ is Asp,Asn, Ser, Thr, or Trp; Xaa₂ is Asn, Gln, His, lie, Leu, or Lys; Xaa₃ isAla, Asp, Phe, Trp, or Tyr; and Xaa₄ is Asp, Gly, Leu, Phe, Ser, or Thras described in U.S. Patent Application 2003/0069395 (incorporatedherein by reference in its entirety) or Dennis et al. (Dennis, M. S.,Zhang, M., Meng, Y. G., Kadkhodayan, M., Kirchhofer, D., Combs, D. &Damico, L. A. (2002) J Biol Chem 277, 35035-35043).

In other embodiments, albumin itself (Osborn, B. L. et al., 2002, J.Pharmacol. Exp. Ther. 303, 540-548), or a biological active fragment ofalbumin can be used as conjugation partner of a mutein of thedisclosure. The term “albumin” includes all mammal albumins such ashuman serum albumin or bovine serum albumin or rat albumin. The albuminor fragment thereof can be recombinantly produced as described in U.S.Pat. No. 5,728,553 or European Patent Applications EP 0 330 451 and EP 0361 991 (incorporated herein by reference in their entirety).Recombinant human albumin (Recombumin®) Novozymes Delta Ltd.(Nottingham, UK) can be conjugated or fused to a mutein of thedisclosure in order to extend the half-life of the mutein.

If the albumin-binding protein is an antibody fragment it may be adomain antibody. Domain Antibodies (dAbs) are engineered to allowprecise control over biophysical properties and in vivo half-life tocreate the optimal safety and efficacy product profile. DomainAntibodies are for example commercially available from Domantis Ltd.(Cambridge, UK and MA, USA).

Using transferrin as a moiety to extend the serum half-life of themuteins of the disclosure, the muteins can be genetically fused to the Nor C terminus, or both, of non-glycosylated transferrin.Non-glycosylated transferrin has a half-life of 14-17 days, and atransferrin fusion protein will similarly have an extended half-life.The transferrin carrier also provides high bioavailability,biodistribution and circulating stability. This technology iscommercially available from BioRexis (BioRexis PharmaceuticalCorporation, PA, USA). Recombinant human transferrin (DeltaFerrin™) foruse as a protein stabilizer/half-life extension partner is alsocommercially available from Novozymes Delta Ltd. (Nottingham, UK).

If an Fc part of an immunoglobulin is used for the purpose to prolongthe serum half-life of the muteins of the disclosure, the SynFusion™technology, commercially available from Syntonix Pharmaceuticals, Inc(MA, USA), may be used. The use of this Fc-fusion technology allows thecreation of longer-acting biopharmaceuticals and may for example consistof two copies of the mutein linked to the Fc region of an antibody toimprove pharmacokinetics, solubility, and production efficiency.

Yet another alternative to prolong the half-life of the muteins of thedisclosure is to fuse to the N- or C-terminus of the muteins long,unstructured, flexible glycine-rich sequences (for example poly-glycinewith about 20 to 80 consecutive glycine residues). This approachdisclosed in WO2007/038619, for example, has also been term “rPEG”(recombinant PEG).

If polyalkylene glycol is used as conjugation partner, the polyalkyleneglycol can be substituted, unsubstituted, linear or branched. It canalso be an activated polyalkylene derivative. Examples of suitablecompounds are polyethylene glycol (PEG) molecules as described in WO99/64016, in U.S. Pat. No. 6,177,074 or in U.S. Pat. No. 6,403,564 inrelation to interferon, or as described for other proteins such asPEG-modified asparaginase, PEG-adenosine deaminase (PEG-ADA) orPEG-superoxide dismutase (see for example, Fuertges et al. (1990) TheClinical Efficacy of Poly(Ethylene Glycol)-Modified Proteins J. Control.Release 11, 139-148). The molecular weight of such a polymer, such aspolyethylene glycol, may range from about 300 to about 70.000 Dalton,including, for example, polyethylene glycol with a molecular weight ofabout 10.000, of about 20.000, of about 30.000 or of about 40.000Dalton. Moreover, as e.g. described in U.S. Pat. No. 6,500,930 or6,620,413, carbohydrate oligo- and polymers such as starch orhydroxyethyl starch (HES) can be conjugated to a mutein of thedisclosure for the purpose of serum half-life extension.

In addition, a mutein disclosed herein may be fused to a moiety mayconfer new characteristics to the muteins of the disclosure such asenzymatic activity or binding affinity for other molecules. Examples ofsuitable fusion partners are alkaline phosphatase, horseradishperoxidase, gluthation-S-transferase, the albumin-binding domain ofprotein G, protein A, antibody fragments, oligomerization domains ortoxins.

In particular, it may be possible to fuse a mutein disclosed herein witha separate enzyme active site such that both “components” of theresulting fusion protein together act on a given therapeutic target. Thebinding domain of the mutein attaches to the disease-causing target,allowing the enzyme domain to abolish the biological function of thetarget.

The present disclosure also relates to nucleic acid molecules (DNA andRNA) that include nucleotide sequences encoding the muteins of thedisclosure. Since the degeneracy of the genetic code permitssubstitutions of certain codons by other codons specifying the sameamino acid, the disclosure is not limited to a specific nucleic acidmolecule encoding a mutein as described herein but encompasses allnucleic acid molecules that include nucleotide sequences encoding afunctional mutein. In this regard, the present disclosure providesnucleotide sequences, as shown in SEQ ID NOs: 41-79, 94-100, encodingsome muteins of the disclosure.

In one embodiment of the disclosure, the method includes subjecting thenucleic acid molecule to mutagenesis at nucleotide triplets coding forat least one, or even more amino acids, of the sequence positionscorresponding to the sequence positions 8, 9, 28, 36, 38, 40, 41, 42,44, 46, 47, 49, 52, 54, 62, 65, 66, 68, 70, 71, 72, 73, 75, 76, 77, 79,80, 81, 83, 87, 96, 97, 98, 100, 103, 105, 106, 108, 111, 112, 114, 123,125, 126, 127, 129, 132, 134, 135, 136, 145, 146, 175, 176, 177 and 178of the linear polypeptide sequence of human NGAL (SEQ ID NO: 1).

The disclosure also includes nucleic acid molecules encoding the muteinsof the disclosure, which include additional mutations outside theindicated sequence positions of experimental mutagenesis. Such mutationsare often tolerated or can even prove to be advantageous, for example ifthey contribute to an improved folding efficiency, serum stability,thermal stability or ligand binding affinity of the muteins.

A nucleic acid molecule disclosed in this application may be “operablylinked” to a regulatory sequence (or regulatory sequences) to allowexpression of this nucleic acid molecule.

A nucleic acid molecule, such as DNA, is referred to as “capable ofexpressing a nucleic acid molecule” or capable “to allow expression of anucleotide sequence” if it includes sequence elements which containinformation regarding to transcriptional and/or translationalregulation, and such sequences are “operably linked” to the nucleotidesequence encoding the polypeptide. An operable linkage is a linkage inwhich the regulatory sequence elements and the sequence to be expressedare connected in a way that enables gene expression. The precise natureof the regulatory regions necessary for gene expression may vary amongspecies, but in general these regions include a promoter which, inprokaryotes, contains both the promoter per se, i.e. DNA elementsdirecting the initiation of transcription, as well as DNA elementswhich, when transcribed into RNA, will signal the initiation oftranslation. Such promoter regions normally include 5′ non-codingsequences involved in initiation of transcription and translation, suchas the −35/−10 boxes and the Shine-Dalgarno element in prokaryotes orthe TATA box, CAAT sequences, and 5′-capping elements in eukaryotes.These regions can also include enhancer or repressor elements as well astranslated signal and leader sequences for targeting the nativepolypeptide to a specific compartment of a host cell.

In addition, the 3′ non-coding sequences may contain regulatory elementsinvolved in transcriptional termination, polyadenylation or the like.If, however, these termination sequences are not satisfactory functionalin a particular host cell, then they may be substituted with signalsfunctional in that cell.

Therefore, a nucleic acid molecule of the disclosure can include aregulatory sequence, such as a promoter sequence. In some embodiments anucleic acid molecule of the disclosure includes a promoter sequence anda transcriptional termination sequence. Suitable prokaryotic promotersare, for example, the tet promoter, the lacUV5 promoter or the T7promoter. Examples of promoters useful for expression in eukaryoticcells are the SV40 promoter or the CMV promoter.

The nucleic acid molecules of the disclosure can also be part of avector or any other kind of cloning vehicle, such as a plasmid, aphagemid, a phage, a baculovirus, a cosmid or an artificial chromosome.

In one embodiment, the nucleic acid molecule is included in a phasmid. Aphasmid vector denotes a vector encoding the intergenic region of atemperent phage, such as M13 or f1, or a functional part thereof fusedto the cDNA of interest. After superinfection of the bacterial hostcells with such an phagemid vector and an appropriate helper phage (e.g.M13K07, VCS-M13 or R408) intact phage particles are produced, therebyenabling physical coupling of the encoded heterologous cDNA to itscorresponding polypeptide displayed on the phage surface (see e.g.Lowman, H. B. (1997) Annu. Rev. Biophys. Biomol. Struct. 26, 401-424, orRodi, D. J., and Makowski, L. (1999) Curr. Opin. Biotechnol. 10, 87-93).

Such cloning vehicles can include, aside from the regulatory sequencesdescribed above and a nucleic acid sequence encoding a mutein asdescribed herein, replication and control sequences derived from aspecies compatible with the host cell that is used for expression aswell as selection markers conferring a selectable phenotype ontransformed or transfected cells. Large numbers of suitable cloningvectors are known in the art, and are commercially available.

The DNA molecule encoding a mutein as described herein, and inparticular a cloning vector containing the coding sequence of such amutein can be transformed into a host cell capable of expressing thegene. Transformation can be performed using standard techniques. Thus,the disclosure is also directed to a host cell containing a nucleic acidmolecule as disclosed herein.

The transformed host cells are cultured under conditions suitable forexpression of the nucleotide sequence encoding a fusion protein of thedisclosure. Suitable host cells can be prokaryotic, such as Escherichiacoli (E. coli) or Bacillus subtilis, or eukaryotic, such asSaccharomyces cerevisiae, Pichia pastoris, SF9 or High5 insect cells,immortalized mammalian cell lines (e.g., HeLa cells or CHO cells) orprimary mammalian cells.

The disclosure also relates to a method for the production of a muteinas described herein, wherein the mutein or polypeptide, a fragment ofthe mutein or a fusion protein of the mutein is produced starting fromthe nucleic acid coding for the mutein or polypeptide by means ofgenetic engineering methods. The method can be carried out in vivo, themutein or polypeptide can for example be produced in a bacterial oreucaryotic host organism and then isolated from this host organism orits culture. It is also possible to produce a protein in vitro, forexample by use of an in vitro translation system.

When producing the mutein in vivo a nucleic acid encoding such mutein orpolypeptide is introduced into a suitable bacterial or eukaryotic hostorganism by means of recombinant DNA technology (as already outlinedabove). For this purpose, the host cell is first transformed with acloning vector that includes a nucleic acid molecule encoding a muteinas described herein using established standard methods. The host cell isthen cultured under conditions, which allow expression of theheterologous DNA and thus the synthesis of the correspondingpolypeptide. Subsequently, the polypeptide is recovered either from thecell or from the cultivation medium.

In some embodiments, a nucleic acid molecule, such as DNA, disclosed inthis application may be “operably linked” to another nucleic acidmolecule of the disclosure to allow expression of a fusion protein ofthe disclosure. In this regard, an operable linkage is a linkage inwhich the sequence elements of the first nucleic acid molecule and thesequence elements of the second nucleic acid molecule are connected in away that enables expression of the fusion protein as a singlepolypeptide.

In addition, in some embodiments, the naturally occurring disulfide bondbetween Cys 76 and Cys 175 may be removed in hNGAL muteins of thedisclosure. Accordingly, such muteins can be produced in a cellcompartment having a reducing redox milieu, for example, in thecytoplasma of Gram-negative bacteria.

In case a mutein of the disclosure includes intramolecular disulfidebonds, it may be preferred to direct the nascent polypeptide to a cellcompartment having an oxidizing redox milieu using an appropriate signalsequence. Such an oxidizing environment may be provided by the periplasmof Gram-negative bacteria such as E. coli, in the extracellular milieuof Gram-positive bacteria or in the lumen of the endoplasmatic reticulumof eukaryotic cells and usually favors the formation of structuraldisulfide bonds.

It is, however, also possible to produce a mutein of the disclosure inthe cytosol of a host cell, preferably E. coli. In this case, the muteinor polypeptide can either be directly obtained in a soluble and foldedstate or recovered in form of inclusion bodies, followed by renaturationin vitro. A further option is the use of specific host strains having anoxidizing intracellular milieu, which may thus allow the formation ofdisulfide bonds in the cytosol (Venturi et al. (2002) J. Mol. Biol. 315,1-8).

However, the mutein or polypeptide as described herein may notnecessarily be generated or produced only by use of genetic engineering.Rather, such mutein or polypeptide can also be obtained by chemicalsynthesis such as Merrifield solid phase polypeptide synthesis or by invitro transcription and translation. It is for example possible thatpromising mutations are identified using molecular modeling and then tosynthesize the wanted (designed) polypeptide in vitro and investigatethe binding activity for CGRP. Methods for the solid phase and/orsolution phase synthesis of proteins are well known in the art (see e.g.Bruckdorfer, T. et al. (2004) Curr Pharm. Biotechnol. 5, 29-43).

In another embodiment, the mutein or polypeptide of the disclosure maybe produced by in vitro transcription/translation employingwell-established methods known to those skilled in the art.

The skilled worker will appreciate methods useful to prepare muteins orpolypeptides thereof contemplated by the present disclosure but whoseprotein or nucleic acid sequences are not explicity disclosed herein. Asan overview, such modifications of the amino acid sequence include,e.g., directed mutagenesis of single amino acid positions in order tosimplify sub-cloning of a mutated hNGAL gene or its parts byincorporating cleavage sites for certain restriction enzymes. Inaddition, these mutations can also be incorporated to further improvethe affinity of a mutein for its target (e.g. CGRP). Furthermore,mutations can be introduced to modulate certain characteristics of themutein such as to improve folding stability, serum stability, proteinresistance or water solubility or to reduce aggregation tendency, ifnecessary. For example, naturally occurring cysteine residues may bemutated to other amino acids to prevent disulphide bridge formation.

The muteins or polypeptides thereof disclosed herein and theirderivatives can be used in many fields similar to antibodies orfragments thereof. For example, the muteins can be used for labelingwith an enzyme, an antibody, a radioactive substance or any other grouphaving biochemical activity or defined binding characteristics. By doingso, their respective targets or conjugates or fusion proteins thereofcan be detected or brought in contact with them. In addition, muteins orpolypeptides thereof of the disclosure can serve to detect chemicalstructures by means of established analytical methods (e.g., ELISA orWestern Blot) or by microscopy or immunosensorics. In this regard, thedetection signal can either be generated directly by use of a suitablemutein conjugate or fusion protein or indirectly by immunochemicaldetection of the bound mutein via an antibody.

Additional objects, advantages, and features of this disclosure willbecome apparent to those skilled in the art upon examination of thefollowing Examples and the attached Figures thereof, which are notintended to be limiting. Thus, it should be understood that although thepresent disclosure is specifically disclosed by exemplary embodimentsand optional features, modification and variation of the disclosuresembodied therein herein disclosed may be resorted to by those skilled inthe art, and that such modifications and variations are considered to bewithin the scope of this disclosure.

V. EXAMPLES Example 1: Peptide Synthesis and Biotinylation of CalcitoninGene-Related Peptides

Calcitonin gene-related peptide (CGRP) is a neuroactive peptide. Itoccurs in two different isoforms, alpha and beta CGRP, and both isoformsfrom human and rat were generated by peptide synthesis (SEQ ID NOs: 80to 83). Peptide solution was aliquoted in siliconized 1.5-mL tube(ThermoFisher, No. 02-681-320) and lyophilized by speed vacuumconcentration system in siliconized 1.5-mL tubes (Thermo Fisher, No.02-681-320). To re-dissolve the peptide 0.5% AcOH were added, and mixedthoroughly by tapping or pipetting.

For selection and screening of muteins of interest, the CGRP peptidesmay be biotinylated. In this regard, a Biotin group was directly coupledto the NH2 group of the N-terminal amino acid of the peptides duringsynthesis.

Example 2: Selection and Identification of Muteins Specifically Bindingto CGRP Using Phage Display and High-Throughput ELISA Screening

hNGAL-based libraries, generated by random mutagenesis of mature hNGAL,were used for selection of muteins specifically binding to the differentCGRP targets. The four biotinylated human and rat CGRP a and 3 formswere used in independent phage display and selection processes either assingle agents over the entire four rounds of selection or were appliedalternatingly.

2×10¹² phagemids from these libraries were incubated with 200 or 500 nMbiotinylated target. Paramagnetic beads coated with neutravidin orstreptavidin were used to capture target/phagemid complexes which weresubsequently isolated with a magnet. Unbound phagemids were removed bywashing the beads with PBST or PBS. Bound phagemids were first elutedwith 300 μl 70 mM triethylamine for 10 min followed by immediateneutralization of the supernatant with 100 μl 1M Tris-Cl pH 6.0. Afterone intermediate wash cycle remaining phagemids were eluted with 100 mMglycine pH 2.2 for 10 min followed by immediate neutralization with 50μl 0.5 M Tris-base. Both elution fractions were pooled and used toinfect 4 mL of E. coli XL1-blue culture (OD₅₅₀ 0.45-0.6) forreamplification. After incubation for 30 min under agitation bacteriawere collected by centrifugation at 5000×g for 2 min, resuspended in 1mL 2×YT medium and plated on three big LB/Amp agar plates (10 g/l bactotryptone, 5 g/l yeast extract, 5 g/l NaCl, pH 7.5, 15 g/l agar, 100μg/mL ampicillin). Plates were incubated overnight at 32° C. Infectedcells were scraped from the agar plates using 50 mL 2×YT mediumsupplemented with 100 μg/mL ampicillin (2×YT/Amp). 50 mL 2×YT/Amp mediumwere inoculated with the appropriate volume of bacterial suspension toreach an OD₅₅₀ of 0.08. The culture was incubated at 37° C. on a shaker(160 rpm) until an OD₅₅₀ of 0.5 was reached and then infected withhelperphages (1.5×10¹¹ pfu) by incubation for 15 min with gentleagitation and for 45 min on a shaker at 37° C. Subsequently, kanamycinwas added to a final concentration of 70 μg/mL to select bacteriainfected by helperphages. Finally, expression of the pIII-hNGAL muteinswas induced by addition of 25 ng/mL anhydrotetracyclin.

After 15 h incubation at 24° C. the supernatant of the culture wascleared by centrifugation (5000×g for 20 min). Subsequently, 20 mLsupernatant were passed through a polyethersulfone membrane with a poresize of 0.22 μm. To the filtrate 5 mL of a solution containing 20% (w/v)PEG-8000 and 15% (w/v) NaCl in water was added and gently mixed. Thesolution was incubated for 30 min on ice before centrifugation for 20min at 4° C. & 5000×g. The pellet containing the phagemids was dissolvedin 1 mL buffer containing 200 mM boric acid, 160 mM NaCl and 1 mM EDTA.Unsoluble particles were removed by centrifugation (5000×g for 5 min).The supernatant was transferred to a fresh tube and mixed with 200 μl ofa solution containing 20% (w/v) PEG-8000 and 15% (w/v) NaCl in water.The solution was incubated 30 min on ice and precipitated phagemids weresubsequently collected by centrifugation (5000×g for 5 min). Phagemidswere resuspended in PBS supplemented with 50 mM benzamidine and used forthe next round of phagemid selection. Four consecutive rounds ofselection were performed.

Phagemid DNA was prepared from E. coli cells infected with the output ofthe fourth selection round and the hNGAL mutein cassette was isolated bydigestion of the DNA with BstX1 and subsequent purification via agarosegel electrophoresis using standard methods (Sambrook et al., (1989)Molecular cloning: a laboratory manual). The hNGAL mutein cassette wasinserted into the likewise cut vector, which allows bacterial productionof the hNGAL muteins under the control of a tetracyclin promoter.CaCl₂-competent TG1-F-cells were transformed with the ligation mixtureand plated on LB/Amp plates.

For optimization of CGRP-specific muteins, libraries were generatedbased on mutein SEQ ID NO: 4, and SEQ ID NO: 5 using either a biasedrandomization of selected positions or error prone polymerase chainreaction (PCR) based methods. The biased design was made such that foreach of the selected positions the amino acid encoded corresponds to theamino acid found in the respective mother clone with a probability of50-70%, while it can be a different amino acid with a 50-30%probability. With N the number of targeted positions and B as bias, themost probable number of exchanges per clone is N×(1−B). In order tofacilitate expression in eukaryotic cells, the hNGAL-derived naturalN-glycosylation site N65 was removed by the mutation N65D; and as forother potential N-glycosylation sites (Asn-X-Ser/Thr), the likelyhood tooccur was reduced by setting a bias at those library positions.

Phage display was employed to select for optimized muteins with improvedheat stability and binding affinity. The phagemid selection wasconducted with increased stringency compared to the initial muteinselections and involved preincubation steps at elevated temperature andlimiting target concentration.

To further optimize binding affinities of CGRP-specific muteins,additional libraries were generated based on mutein SEQ ID NO: 14, andSEQ ID NO: 11 using an error prone polymerase chain reaction (PCR) basedmethod for SEQ ID NO: 14 and a biased randomization of selectedpositions for SEQ ID NO: 11. The biased design was made exactly asdescribed before.

Phage display was employed to select for optimized muteins with improvedheat stability and binding affinity. The phagemid selection wasconducted with increased stringency compared to the initial muteinselections and involved preincubation steps at elevated temperature andlimiting target concentration.

In order to facilitate expression in E. coli, the endogenous disulfidebond was removed. Libraries were generated based on mutein SEQ ID NO:17, and SEQ ID NO: 27 using a biased randomization of positions Cysteine76 and Cysteine 175 by employing TRIM oligonucleotides. Selection ofmuteins was performed as described but with increased stringency.

Individual colonies, which were obtained through the each selectionprocess described above, were used to inoculate 2×YT/Amp medium andgrown overnight (14-18 h) to stationary phase. Subsequently, 50 μl2×YT/Amp were inoculated from the stationary phase cultures andincubated for 3 h at 37° C. and then shifted to 22° C. until an OD₅₉₅ of0.6-0.8 was reached. Production of muteins was induced by addition of 10μl 2×YT/Amp supplemented with 1.2 μg/mL anhydrotetracyclin. Cultureswere incubated at 22° C. until the next day. After addition of 40 μl of5% (w/v) BSA in PBS/T and incubation for 1 h at 25° C. cultures wereready for use in screening assays. While 20 μl of the cultures weredirectly applied to the screening ELISA plate, the residual volume wasincubated at 65° C. for 1 h.

Binding of the isolated muteins to CGRP was tested by coating a 1:1mixture of neutravidin and streptavidin (5 μg/mL in PBS) overnight at 4°C. on microtiterplates. After blocking the plate with 2% BSA in PBSTbiotinylated CGRP was captured on the coated microtiterplates at aconcentration of 1 μg/mL in PBS/T. Subsequently, 20 μl of BSA-blockedcultures (with or without previous heat incubation) were added to themicrotiter plates and incubated for 1 h at 25° C. Bound muteins weredetected with anti-Streptag antibody conjugated with horseradishperoxidase (1 h incubation; IBA, Boettingen). For quantification, 20 μlof QuantaBlu fluorogenic peroxidase substrate was added and thefluorescence was determined at an excitation wavelength of 330 nm and anemission wavelength of 420 nm.

In addition, reverse screening formats were applied, where the muteinswere captured via the strep-tag on microtiter plates coated withanti-Streptag antibody and different concentrations of biotinylatedtarget were added and detected via Extravidin-HRP (E2886; Sigma).

To select for muteins with increased affinity and stability screeningwas performed with i) reduced antigen concentration and/or ii)competition with unbiotinylated target and/or iii) incubation of thescreening supernatant at 65° C. or 70° C. before addition to the targetplate and/or iv) using reverse screening formats were the muteins werecaptured via the Streptag on microtiter plates coated with anti-Streptagantibody and different concentrations of biotinylated target was addedand detected via extravidin-HRP (Sigma Aldrich, St. Louis, Mo.).

Clones which showed positive signals in ELISA screening described abovewere then sequenced and muteins were selected for furthercharacterization. Amino acid sequences of selected muteins are shown inSEQ ID NOs: 2-40.

Example 3: Expression and Purification of Muteins

Muteins obtained from Example 2 (SEQ ID NOs: 2-40), for which nucleotidesequences coding are shown in SEQ ID NOs: 41-79, were expressed withC-terminal tag SAWSHPQFEK (SEQ ID NO: 84); including the SA linker andthe Strep-Tag® II, WSHPQFEK (SEQ ID NO: 85) in E. coli in 2YT-Amp mediumto purify the muteins after expression using Streptactin affinitychromatography and preparative size exclusion chromatography.

Example 4: Affinity of Muteins to Soluble Human and Rat CGRP Determinedin an ELISA Based Setting

Binding of lipocalin muteins to alpha and beta CGRP from human and ratin solution was tested in vitro using a competition ELISA assay format(FIG. 1). In this experiment, a constant concentration ofnon-biotinylated CGRP (0.5 μM) was incubated for 1 h with variableconcentrations of lipocalin muteins SEQ ID NO: 2, SEQ ID NO: 3, SEQ IDNO: 4; SEQ ID NO: 5, and SEQ ID NO: 6. After this pre-incubation insolution, an aliquot of the lipocalin mutein/CGRP mixture wastransferred to an ELISA plate coated with Neutravidin-captured humanalpha CGRP-bio to measure the concentration of lipocalin muteins thatwas not blocked by non-biotinylated human alpha CGRP (SEQ ID NO: 80) andtherefore could still be bound by the immobilized human alpha CGRP-bio(FIG. 1). This procedure was performed on another relevant CGRP species(human beta CGRP (SEQ ID NO: 81), rat alpha CGRP (SEQ ID NO: 82), ratbeta CGRP (SEQ ID NO: 83)). All incubation steps were performed withshaking at 300 rpm, and the plate was washed after each incubation stepwith 80 μL PBS-T buffer (PBS, 0.05% Tween 20) for five times using aBiotek ELx405 select CW washer. In the first step, a 384-well ELISAplate was coated with 20 μL of Neutravidin at a concentration of 5 μg/mLin PBS over night at 4° C. After washing, the plate was blocked with 60μL PBS-T/BSA (2% BSA in PBS containing 0.05% Tween 20) for 1 h at roomtemperature.

To allow for detection and quantification of plate-bound lipocalinmuteins, the residual supernatants were discarded and 20 μL HRP-labeledanti-hNGAL antibody was added at a predetermined optimal concentrationin PBS-T/BSA and incubated for 1 h at RT. The anti-hNGAL antibody hadbeen obtained by immunization of rabbits with a mixture of muteins, andwas subsequently coupled to HRP using a kit (EZ-link Plus ActivatedPeroxidase, Thermo Scientific) according to the manufacturer'sinstructions, to obtain the antibody-HRP conjugate. After washing, 20 μlfluorogenic HRP substrate (QuantaBlu, Thermo) was added to each well,and the reaction was allowed to proceed for 15 to 60 minutes. Thefluorescence intensity of every well on the plate was read using afluorescence microplate reader (Tecan or Molecular Devices). To evaluatethe data, free mutein concentration, c(mutein)_(free), was calculatedbased on the standard curve results, and plotted versus ligandconcentration, c(Ligand). To obtain the ligand concentration at whichformation the ligand/mutein complex was blocked by 50% (IC50), thecurves were fitted by nonlinear regression with a single-sites bindingmodel according to c(mutein)_(free)=c(mutein)_(tot)/(1+c(Ligand)/IC50)),with the total tracer concentration c(mutein)_(tot) and the IC50 valueas free parameters. Curve fitting was performed using GraphPad Prism 4software.

The resulting IC₅₀ values are summarized in Table 1. Muteins selectedbind to all subtypes of the respective CGRP species as shown in FIG. 1.

TABLE 1 IC₅₀ values in a competition ELISA assay Human Human Rat Ratalpha CGRP beta CGRP alpha CGRP beta CGRP SEQ ID NO IC50 [nM] IC50 [nM]IC50 [nM] IC50 [nM] SEQ ID NO: 2 55 46 35 47 SEQ ID NO: 3 7.5 14 >100012 SEQ ID NO: 4 2.1 1.8 2.6 3 SEQ ID NO: 5 36 28 21 27 SEQ ID NO: 63.1 >1000 0.77 1.6

Example 5: Affinity of Optimized Muteins Binding to CGRP Determined bySPR

SPR was used to measure binding kinetics and affinity of the optimizedlipocalin muteins disclosed herein.

SPR analysis of the binding of the hNGAL muteins to human and rat CGRPalpha and beta was performed at 37° C. on a Biacore T200 instrument (GEHealthcare) using HBS-EP+ (1×; BR-1006-69; GE Healthcare) as runningbuffer.

The Biotin CAPture Kit (GE Healthcare) was used to immobilizebiotinylated lipocalin muteins to a chip surface. Muteins werebiotinylated using standard NHS chemistry. Undiluted Biotin CAPtureReagent (streptavidin conjugated with ss-DNA oligo) was captured on aSensor Chip CAP with the pre-immobilized complementary ss-DNA oligo.Thereafter, biotinylated muteins at 1 μg/mL were applied for 300 s at aflow rate of 5 μL/min.

CGRP species were applied in three concentrations of 30 nM, 3 nM and 0.3nM at a flow rate of 30 μL/min or in a single concentration of 25 nM percycle as shown in FIG. 2. The dilutions were injected with associationtimes of 180 s and dissociation times of 5400 sec to obtain ka and kdinformation. Regeneration of the chip surface was achieved by injecting6 M Guanidinium-HCl+0.25 M NaOH (120 s) with a flow rate of 10 μL/min.Injection of regeneration solutions was followed by an extra wash stepwith HBS-EP+(1×; BR-1006-69; GE Healthcare) running buffer and astabilization period of 120 s.

The data were double-referenced by subtraction of the correspondingsignals measured for the control channel (loaded with Biotin CAPturereagent only) and by subtraction of buffer injections from the bindingresponses. Association rate constant ka and dissociation rate constantkd for the binding reaction were determined using Biacore T200Evaluation Software V2.0 for data processing and kinetic fitting. Thedata were globally fit with 1:1 binding model.

The values determined for ka, kd and the resulting equilibriumdissociation constant KD for SEQ ID NO: 4, SEQ ID NOs: 7 to 17, and SEQID NOs: 19 to 28 are summarized in Table 2. A graphical representationof the results is shown in FIG. 2A to 2D, for human and rat alpha andbeta CGRP, respectively. Optimized CGRP specific lipocalin muteins bindboth isoforms of human and rat CGRP with picomolar to low nanomolaraffinity and affinities are up to 120-fold improved after optimization,while no significant binding of hNGAL wildtype (SEQ ID NO:1) as acontrol is detected.

TABLE 2 Affinities, association rate constants ka and dissociation rateconstants kd of optimized muteins for human and rat CGRP species asdetermined by SPR. human αCGRP human βCGRP rat αCGRP rat βCGRP SEQ ka kdKD ka kd KD ka kd KD ka kd KD ID NO: [M⁻¹ · s⁻¹] [s⁻¹] [nM] [M⁻¹ · s⁻¹][s⁻¹] [nM] [M⁻¹ · s⁻¹] [s⁻¹] [nM] [M⁻¹ · s⁻¹] [s⁻¹] [nM] 4 1.66E+063.02E−03 1.82 5.24E+06 3.95E−03 0.753 1.24E+06 6.21E−03 5.00 1.66E+063.65E−03 2.19 7 3.74E+06 2.49E−04 0.067 5.21E+06 1.88E−04 0.036 1.04E+063.13E−04 0.30 3.04E+06 2.76E−04 0.091 8 2.07E+06 5.95E−04 0.288 3.70E+065.29E−04 0.143 7.34E+05 8.37E−04 1.14 1.82E+06 6.36E−04 0.349 9 5.88E+062.57E−04 0.044 6.80E+06 1.81E−04 0.027 1.22E+06 3.18E−04 0.26 3.68E+062.75E−04 0.075 10 1.26E+06 2.05E−04 0.163 2.14E+06 1.62E−04 0.0765.59E+05 3.07E−04 0.55 1.08E+06 2.24E−04 0.206 11 3.08E+06 4.55E−050.015 7.91E+06 5.63E−05 0.007 9.84E+05 7.60E−05 0.08 1.74E+06 7.30E−050.042 12 1.08E+06 1.62E−04 0.15 1.10E+06 1.04E−04 0.095 6.61E+052.99E−04 0.45 1.17E+06 2.05E−04 0.176 13 5.82E+06 4.36E−04 0.0751.18E+07 3.66E−04 0.031 1.85E+06 5.25E−04 0.28 3.16E+06 3.50E−04 0.11114 2.56E+06 1.41E−04 0.055 4.56E+06 1.41E−04 0.031 1.19E+06 3.39E−040.29 1.69E+06 1.81E−04 0.107 15 6.32E+06 2.38E−04 0.038 1.53E+072.73E−04 0.018 1.59E+06 2.74E−04 0.17 4.98E+06 1.93E−04 0.039 165.02E+06 2.59E−04 0.052 1.01E+07 3.64E−04 0.036 1.41E+06 3.98E−04 0.282.37E+06 2.29E−04 0.097 25 2.68E+06 1.65E−05 0.006 2.02E+06 1.01E−050.005 1.30E+06 2.12E−05 0.016 1.64E+06 1.33E−05 0.008 24 1.60E+061.40E−05 0.009 2.52E+06 9.01E−06 0.004 1.43E+06 2.08E−05 0.015 1.69E+061.22E−05 0.007 23 1.64E+06 1.84E−05 0.011 2.84E+06 4.11E−06 0.0011.39E+06 1.30E−05 0.009 1.74E+06 1.34E−05 0.008 26 1.50E+06 1.99E−050.013 2.44E+06 7.60E−06 0.003 1.31E+06 2.01E−05 0.015 1.56E+06 9.98E−060.006 27 1.43E+06 2.59E−05 0.018 2.04E+06 2.26E−05 0.011 8.07E+053.10E−05 0.038 1.50E+06 2.64E−05 0.018 28 1.59E+06 4.99E−05 0.0312.52E+06 3.41E−05 0.014 1.41E+06 6.88E−05 0.049 1.72E+06 5.48E−05 0.03219 2.26E+06 1.07E−05 0.005 4.56E+06 6.67E−06 0.001 1.25E+06 3.02E−050.024 2.01E+06 1.21E−05 0.006 22 1.76E+06 1.56E−05 0.009 2.70E+069.32E−06 0.003 9.31E+05 3.05E−05 0.033 1.60E+06 2.02E−05 0.013 173.34E+06 3.66E−05 0.011 1.36E+07 1.44E−05 0.001 2.75E+06 8.44E−05 0.0315.18E+06 5.99E−05 0.012 20 1.45E+06 1.75E−05 0.012 2.18E+06 7.89E−060.004 8.67E+05 2.41E−05 0.028 1.38E+06 1.84E−05 0.013 21 1.21E+061.71E−05 0.014 2.36E+06 8.74E−06 0.004 7.03E+05 3.70E−05 0.053 1.34E+062.36E−05 0.018

Example 6: Functional Testing of Muteins Binding to CGRP in a cAMP Assay

The ability of the lipocalin muteins of SEQ ID NO: 11, SEQ ID NO: 14,SEQ ID NOs: 17 to 20, and SEQ ID NOs: 23 to 27 to neutralize thebiological activity of human and rat CGRP was assessed by measuringcAMP, a second messenger, production in human SK-N-MC (Human brainneuroepithelioma) and in rat L6 (Rat skeletal muscle myoblasts),respectively, in response to CGPR treatment using HitHunter® c-AMP XS+Kit (DiscoverX).

In this experiment, a constant concentration of human or rat CGRP wasincubated with variable concentrations of lipocalin muteins for 90minutes. After this pre-incubation in solution, an aliquot of thelipocalin mutein/CGRP mixture was incubated with SK-N-MC or L6 cells,respectively, to measure the residual CGRP induced cAMP production.

SK-N-MC cells were maintained in EMEM, supplement with 10% fetal calfserum and were cultured in cell culture flasks under standard conditionsaccording to manufacturer's instruction (ATCC, 37° C., 5% CO₂atmosphere).

L6 cells were maintained in DMEM, supplement with 10% fetal calf serumand were cultured in cell culture flasks under standard conditionsaccording to manufacturer's instruction (ATCC, 37° C., 5% CO₂atmosphere).

The detailed procedure of setting up the assay is hereby described asfollows.

A fixed concentration of human or rat CGRP was incubated in solutionwith varying concentrations of SEQ ID NO: 11, SEQ ID NO: 14, SEQ ID NOs:17 to 20, and SEQ ID NOs: 23 to 27 using a suitable startingconcentration which was serially diluted at a 1:3 ratio down to thepicomolar range in serum free culture media containing 0.5 mM IBMX and0.1% BSA (Working Buffer). After 90 min incubation at room temperature,5 μl of the reaction mixture was transferred in a white 384 well plate,which subsequently was preheated for 10 min at 37° C., 5% CO2 directlybefore cell addition.

The adherent cells, human SK-N-MC or rat L6, cells were dissociated fromtheir substrate with accutase and resuspended in PBS. Subsequently,cells were centrifuged down for 5 minutes at 300 g, and cell number wasadjusted to 3×10⁶ cells/mL in Antibody Working Solution (2/3 WorkingBuffer, 1/3 HitHunter® Antibody Solution) according to manufacturer'sinstruction.

30.000 cells/well (10 μl) were added to the plate and covered with gaspermeable adhesive seal.

cAMP production was then allowed 30 min at 37° C., 5% CO2.

Subsequently, 20 μl ED/Lysis/CL Working Solution (19 parts Lysis Buffer,1 part Galacton Star, 5 parts Emerald, 25 parts cAMP XS+ED Reagent) wereadded and the plate and incubated for 1 h protected from light at roomtemperature.

20 μl EA reagent were added to the cells in each of the wells, andluminescence was measured after 1-18 h using the PheraStar.

Evaluation and curve fitting was performed using GraphPad Prism 4software. A graphical representation of the results is shown in FIG. 3Ato 3D, for human and rat alpha and beta CGRP, respectively. Theresulting IC50 values are summarized in Table 3 below.

TABLE 3 IC50 values of muteins from a functional cAMP assay using humanand rat CGRP species. SEQ human αCGRP human βCGRP rat αCGRP rat βCGRP IDNO IC50 [nm] IC50 [nM] IC50 [nM] IC50 [nM] 11 0.11 0.22 0.08 0.06 27 0.10.12 — — 25 0.15 0.19 0.06 0.16 24 0.12 0.19 0.07 0.16 23 0.18 0.2 0.070.17 26 0.16 0.26 0.05 0.16 14 0.15 1.5 0.12 0.09 19 0.14 0.21 0.07 0.1720 0.14 0.17 0.08 0.11 18 0.19 0.29 0.06 0.14 17 0.11 0.23 0.06 0.11

Example 7: Characterization of Cysteine-Free Lipocalin Muteins Specificfor CGRP

Biacore affinities of CGRP-specific muteins (SEQ ID NO: 17, SEQ ID NO:27, and cysteine-free muteins SEQ ID NOs: 29 to 40) towards human alphaand beta CGRP were determined by using SPR method as identicallydescribed in Example 5. The resulting KD values are listed in Table 4.

A cAMP assay was employed in the same way as described in Example 6 todetermine the functional potency of CGRP-specific muteins SEQ ID NO: 17,SEQ ID NO: 27, and cysteine-free muteins SEQ ID NOs: 29 to 40 (see FIGS.4A and 4B). The resulting IC50 values for human alpha and beta CGRPspecies are summarized in Table 4.

A fluorescence-based thermal denaturation assay (commonly referred to asThermal shift assay of differential scanning fluorometry) was employedto measure the thermal stability of CGRP-specific muteins (SEQ ID NO:17, SEQ ID NO: 27, and cysteine-free muteins SEQ ID NOs: 29 to 40) usingMx3005P qPCR System (Agilent Technologies).

Therefore lipocalin mutein solutions were diluted to a concentration of10 μM in phosphate-buffered saline (PBS; pH 7.4; 10010; LifeTechnologies) and a 15-fold stock solution in PBS of the fluorescent dyeSYPRO Orange (5000× concentrate in DMSO; S-6650; Life technologies) wasprepared. 20 μl of protein dilution was mixed with 5 μl of SYPRO Orangestock in a qPCR plate (FrameStar 96 non skirted; Cat No 4ti-0711;4titude) and the plate was sealed with caps (Flat Optically Clear Caps;Cat No 4Ti-0751; 4titude). Using an Mx3005P qPCR System the plate wasgradually heated from 25° C. to 100° C. (45 s/step) while thefluorescence signal was recorded at an excitation wavelength of 492 nmand an emission wavelength of 610 nm.

An increase in fluorescence indicates protein unfolding, as SYPRO Orangebinds nonspecifically to hydrophobic surfaces and water stronglyquenches the fluorescence of Sypro Orange (James K. Kranz. CelineSchalk-Hihi (2011); “Protein thermal shifts to identify low molecularweight fragments”; Methods Enzymol. 493: 277-298;doi:10.1016B978-0-12-381274-2.00011-X; PMID 21371595).

Savitzky-golay smoothing (5× savitzky golay filter) was applied to theraw data (fluorescence signal over temperature) and the first derivativewas calculated. For determination of the melting temperature Tm themaximum of the first derivative (corresponding to the inflection pointof the fluorescence-over-temperature curve) was read out and matchedwith the corresponding temperature (=Tm). The complete evaluation wasperformed in Microsoft Excel.

The melting temperatures (Tm) of the lipocalin muteins as determined inthe thermal shift assay described above are compiled in Table 4.

TABLE 4 SPR affinities (KD), functional potencies (IC50) and meltingtemperatures (Tm) of cysteine-free muteins are summarized in thefollowing table. cAMP SPR KD [nM] assay IC50 [nM] SEQ ID NO: hαCGRPhβCGRP hαCGRP hβCGRP Tm [° C.] 17 0.020 0.003 0.09 0.13 75 29 0.0650.050 0.14 0.91 69 30 0.109 0.075 0.22 1.32 69 27 0.038 0.007 0.1 0.1280 31 0.033 0.043 0.19 1.64 73 32 0.034 0.021 0.17 0.26 76 33 0.0340.018 0.14 0.24 76 34 0.041 0.025 0.12 0.29 79 35 0.045 0.017 0.15 0.2777 36 0.046 0.022 0.25 0.81 73 37 0.055 0.023 0.16 0.77 72 38 0.0590.026 0.21 3.16 74 39 0.062 0.034 0.21 1.03 76 40 0.070 0.023 0.18 0.4278

Example 8: Preparation of Tag-Free Lipocalin Muteins

With reference to the amino acid sequences of lipocalin muteins (SEQ IDNOs: 34 and 17), tag-free lipocalin muteins were designed as shown inSEQ ID NOs: 87 and 88, respectively. N-terminal Gly was attached inorder to avoid the formation of pyroglutamic acid from Gln, which isoriginally N-terminal amino acid of the mature hNGAL (SEQ ID NO: 1). Toproduce them, nucleotide sequences (SEQ ID NOs: 94 and 95) correspondingto the amino acid sequences of tag-free lipocalin muteins (SEQ ID NOs:87 and 88) were subcloned into E. coli expression vectors. Furthermore,based on the nucleotide sequence (SEQ ID NO: 95), two or more bases weresubstituted by PCR-based site-directed mutagenesis. The resultingnucleotide sequences (SEQ ID NOs: 96-100), which encode lipocalinmuteins (SEQ ID NOs: 89-93), were also subcloned into E. coli expressionvectors.

Using the above-described vectors, E. coli expression was performedusing the medium (MagicMedia™ (Life Technologies)). To facilitatepurification, lipocalin muteins, of which N-terminal amino acid is Gly(SEQ ID NOs: 87-93), were expressed with N-terminal tagMRGSHHHHHHGSENLYFQ (SEQ ID NO: 86) including His₆-tag and a part of theTEV protease-recognition motif which is an amino acid sequenceconsisting of E(Glu) 13 to Q(Gln) 18 of SEQ ID NO: 86, so that eachexpression product could be cleaved by TEV protease of which amino acidsequence and the corresponding nucleotide sequence are shown in SEQ IDNOs: 101 and 102, respectively. The expression products were purified byimmobilized-metal affinity chromatography using TALON CellThru Resin(Clontech), followed by the removal of the tag using TEV protease. TEVprotease cleaved between Q(Gln) and G(Gly), and as a result, purifiedtag-free lipocalin muteins had N-terminal Gly (SEQ ID NOs: 87-93).Further purification was performed by anion exchange chromatographyusing HiTrap Q FF columns (GE Healthcare) and size exclusionchromatography using HiLoad 16/600 Superdex 75 pg column (GEHealthcare).

Example 9: Characterization of Tag-Free Lipocalin Muteins

SPR analysis of the binding of the tag-free muteins to human alpha CGRPwas performed at 37° C. on a Biacore T200 instrument (GE Healthcare)using HBS-EP+ as running buffer.

The Biotin CAPture Kit (GE Healthcare) was used to immobilizedbiotinylated lipocalin muteins to a chip surface. Muteins werebiotinylated using standard NHS chemistry. Fifty-fold diluted BiotinCAPture Reagent (streptavidin conjugated with ss-DNA oligo) was capturedon a Sensor Chip CAP with the pre-immobilized complementary ss-DNAoligo. Thereafter, biotinylated muteins at 200 nM were applied for 60 sat a flow rate of 10 μL/min.

Human alpha CGRP was applied in concentrations ranging from 0.0256 nM to5 nM at a flow rate of 30 μL/min. The dilutions were injected withassociation times of 600 s and dissociation times of 1800 s.Regeneration of the chip surface was achieved by injecting 6 MGuanidinium-HCl+0.25 M NaOH (120 s) with a flow rate of 10 μL/min,followed by injecting 30% acetonitrile+0.25 M NaOH (120 s) with a flowrate of 10 μL/min. Injection of regeneration solutions was followed byan extra wash step with HBS-EP+ running buffer and a stabilizationperiod of 60 s.

The data were double-referenced by subtraction of the correspondingsignals measured for the control channel (loaded with Biotin CAPturereagent only) and by subtraction of buffer injections from the bindingresponses. Association rate constant ka and dissociation rate constantkd for the binding reaction were determined using Biacore T200Evaluation Software version 1.0 for data processing and kinetic fitting.The data were globally fit with 1:1 binding model.

Resulting KD values for tag-free muteins (SEQ ID NOs: 87-93) are shownin Table 5. A graphical representation of the results is shown in FIG.5.

To determine the functional potency of tag-free muteins SEQ ID NOs: 87to 93, cAMP assay was employed in the same way as described in Example 6with minor modifications as follows: (1) 5,000 cells/well were added tothe plate. (2) Luminescence was measured using EnSpire (Perkin Elmer).

The resulting IC50 values for human alpha CGRP are summarized in Table5.

TABLE 5 SPR affinity (KD) and functional potency (IC50) of tag-freemuteins. SEQ ID NO: SPR KD [nM] cAMP assay IC50 [nM] 87 0.081 0.66 880.008 0.17 89 0.006 0.17 90 0.012 0.16 91 0.010 0.16 92 0.010 0.18 930.011 0.13

Example 10: Effect of Lipocalin Muteins on Rat Skin VasodilatationInduced by Electrical Stimulation of Saphenous Nerve

To test antagonist activity of CGRP specific lipocalin muteins (SEQ IDNOs: 11, 17, 18, 23, 25, 27, 87 and 89), effect of the muteins on skinvasodilatation by stimulation of rat saphenous nerve was tested using arat model (Br J Pharmacol., 1993, 110(2):772-6) with the followingmodifications. Sprague Dawley rats were pre-treated with guanethidinesulfate (20 mg/kg, sc) a day before experiments to block sympatheticactivity. Rats were anaesthetized with thiobutabarbital (100 mg/kg, ip)and maintained with 0.5-1% isoflurane. The saphenous nerve of the hindlimb was exposed surgically, cut proximally and placed over platinumbipolar electrodes for stimulation. During experiment, the nerve wascovered with surgical cotton dipped in liquid paraffin to prevent itfrom drying. Skin blood flow was measured on the mediodorsal side of thehind paw using a skin probe connected to a laser Doppler flow metre.After a stable baseline flux (less than 5% variation) had beenestablished, the distal end of the saphenous nerve was electricallystimulated with 30 pulses (2 Hz, 10V, 1 ms, for 15 sec) 125 minutesafter administration. All muteins and vehicle were administratedsubcutaneously.

All data were recorded using chart software (LabChart 7, ADInstrumentsPty. Ltd.). Cumulative change in skin blood flow was estimated by thearea under the flux-time curve (AUC) for each flux response toelectrical pulse stimulation. Inhibitory effect of muteins on blood flowincrease (AUC) by electrical stimulation was calculated in comparisonwith vehicle treatment group as blood flow inhibition. (shown in Table6)

TABLE 6 rat skin blood flow assay Time after Blood flow Doseadministration inhibition SEQ ID NO: (mg/kg, sc) (min) (% of vehicle) 113 125 79.7 17 3 125 81.9 18 0.3 125 39.1 23 0.3 125 49.9 25 0.3 125 4027 3 125 81.6 87 3 125 69.4 89 2.5 125 64.4

Embodiments illustratively described herein may suitably be practiced inthe absence of any element or elements, limitation or limitations, notspecifically disclosed herein. Thus, for example, the terms“comprising”, “including”, “containing”, etc. shall be read expansivelyand without limitation. Additionally, the terms and expressions employedherein have been used as terms of description and not of limitation, andthere is no intention in the use of such terms and expressions ofexcluding any equivalents of the features shown and described orportions thereof, but it is recognized that various modifications arepossible within the scope of the invention claimed. Thus, it should beunderstood that although the present embodiments have been specificallydisclosed by preferred embodiments and optional features, modificationand variations thereof may be resorted to by those skilled in the art,and that such modifications and variations are considered to be withinthe scope of this invention. All patents, patent applications, textbooksand peer-reviewed publications described herein are hereby incorporatedby reference in their entirety. Furthermore, where a definition or useof a term in a reference, which is incorporated by reference herein isinconsistent or contrary to the definition of that term provided herein,the definition of that term provided herein applies and the definitionof that term in the reference does not apply. Each of the narrowerspecies and subgeneric groupings falling within the generic disclosurealso forms part of the invention. This includes the generic descriptionof the invention with a proviso or negative limitation removing anysubject matter from the genus, regardless of whether or not the excisedmaterial is specifically recited herein. In addition, where features aredescribed in terms of Markush groups, those skilled in the art willrecognize that the disclosure is also thereby described in terms of anyindividual member or subgroup of members of the Markush group. Furtherembodiments will become apparent from the following claims.

Equivalents: Those skilled in the art will recognize, or be able toascertain using no more than routine experimentation, many equivalentsto the specific embodiments of the invention described herein. Suchequivalents are intended to be encompassed by the following claims. Allpublications, patents and patent applications mentioned in thisspecification are herein incorporated by reference into thespecification to the same extent as if each individual publication,patent or patent application was specifically and individually indicatedto be incorporated herein by reference.

1. A human neutrophil gelatinase associated lipocalin (hNGAL) muteinthat is capable of binding CGRP with detectable affinity when measuredin a competition ELISA assay essentially described in Example
 4. 2. ThehNGAL mutein of claim 1, wherein said mutein is capable of (a) bindingCGRP with a K_(D) of about 5 nM or lower when measured by a SurfacePlasmon Resonance based assay essentially described in Example 5, or (b)inhibiting or reducing CGRP induced cAMP production with an IC50 valueof about 5 nM or lower, in a SK-N-MC cell-based functional assayessentially described in Example
 6. 3. The hNGAL mutein of claim 1,wherein said mutein is crossreactive with both human CGRP and rat CGRP.4. The hNGAL mutein of claim 3, wherein said mutein is capable of (a)binding rat CGRP with detectable affinity when measured in a competitionELISA assay essentially described in Example 4, (b) binding rat CGRPwith a K_(D) of about 5 nM or lower when measured by a Surface PlasmonResonance based assay essentially described in Example 5, or (c)inhibiting or reducing rat CGRP induced cAMP production with an IC50value of about 5 nM or lower, in a L6 cell-based functional assayessentially described in Example
 6. 5. The hNGAL mutein of claim 1,wherein said mutein comprises a mutated amino acid residue at one ormore positions corresponding to a sequence positions 8, 9, 28, 36, 38,40, 41, 42, 44, 46, 47, 49, 52, 54, 62, 65, 66, 68, 70-73, 75, 76, 77,79, 80, 81, 83, 87, 96, 97, 98, 100, 103, 105, 106, 108, 111, 112, 114,123, 125, 126, 127, 129, 132, 134, 135, 136, 145, 146, 175, 176, 177 and178 of the linear polypeptide sequence of the mature hNGAL (SEQ IDNO: 1)
 6. The hNGAL mutein of claim 1, wherein the amino acid sequenceof the hNGAL mutein comprises at least one of the following mutatedamino acid residue in comparison with the linear polypeptide sequence ofthe mature hNGAL: Leu 36→Ile, Phe, Trp, Arg or Glu; Ala 40→Met, Trp orThr; Ile 41→Leu, Trp, Gly or Glu; Gln 49→Leu, Phe, Lys, Glu or Thr; Tyr52→Ala, Gly, Glu or Gln; Ser 68→Trp, His or Asp; Leu 70→Met, Trp, Tyr,Gly or Gln; Arg 72→Met, Ile, Trp, Glu or Ser; Lys 73→Ala, Glu, Thr orGln; Asp 77→Ile or Asn; Trp 79→Val, Gly, His or Thr; Arg 81→Gly, His,Glu or Asn; Asn 96→Ala, Gly or Thr; Tyr 100→Ile, Pro or Glu; Leu103→Met, Glu, Thr or Gln; Tyr 106→Leu, Ile, Ala, His or Asn; Lys125→Val, Phe, Gly or Glu: Ser 127→Phe, Trp or Arg; Tyr 132→Leu, Ile orTrp; and Lys 134→Trp, His or Glu.
 7. The hNGAL mutein of claim 1,wherein the amino acid sequence of the hNGAL mutein comprises thefollowing substitution in comparison with the linear polypeptidesequence of the mature hNGAL: Gln 28→His; and Cys 87→Ser.
 8. The hNGALmutein of claim 1, wherein the hNGAL mutein comprises one of thefollowing sets of amino acid substitutions in comparison with the linearpolypeptide sequence of the mature hNGAL: (a) Gln 28→His; Leu 36→Glu;Ala 40→Trp; Ile 41→Gly; Gln 49→Lys; Tyr 52→Ala; Ser 68→Asp; Leu 70→Gln;Arg 72→Ile; Lys 73→Glu; Arg 81→Gly; Cys 87→Ser; Asn 96→Ala; Tyr 100→Glu;Leu 103→Gln; Tyr 106→Asn; Lys 125→Glu; Ser 127 T Trp; Tyr 132→Leu; Lys134→Trp; (b) Gln 28→His; Leu 36→Phe; Ala 40→Met; Ile 41-3 Trp; Gln49→Phe; Tyr 52→Gly; Ser 68→Trp; Leu 70→Trp; Arg 72→Glu; Lys 73→Ala; Trp79→Gly; Arg 81→Asn; Cys 87→Ser; Asn 96→Gly; Tyr 100→Pro; Leu 103 t Met;Tyr 106→His; Lys 125→Glu; Ser 127→Phe; Tyr 132→Trp; Lys 134→Trp; (c) Gln28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Thr; Tyr 52→Gln; Ser68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys 125→Gly;Tyr 132→Ile; Lys 134→Glu; (d) Gln 28→His; Leu 36→Arg; Ile 41→Glu; Gln49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Trp; Lys 73→Gln; Asp77→Ile; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Thr; Tyr 106→Ala;Lys 125→Val; Ser 127→Arg; Tyr 132→Trp; Lys 134→Glu; or (e) Gln 28→His;Leu 36→Ile; Ala 40→Trp; Ile 41→Trp; Gln 49→Leu; Ser 68→His; Leu 70→Met;Arg 72→Met; Lys 73→Thr; Trp 79→Thr; Cys 87→Ser; Tyr 100→Ile; Leu103→Met; Tyr 106→Leu; Lys 125→Phe; Ser 127→Trp; Tyr 132→Trp; Lys134→His.
 9. The hNGAL mutein of claim 1, wherein the amino acid sequenceof the hNGAL mutein comprises the following substitution in comparisonwith the linear polypeptide sequence of the mature hNGAL: Gln 28→His;Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Leu 42→Arg; Asp 47→Asn; Gln 49→Ile,Pro or Thr; Tyr 52→Gln; Thr 54→Met, Ile or Lys; Lys 62→Arg; Asn 65→Asp;Val 66→Ala; Ser 68→Trp; Leu 70→Tyr; Phe 71→Leu; Arg 72→Ala or Ser; Lys73→Asp or Glu; Lys 75→Arg; Asp 77→Arg or Asn; Trp 79→His; Arg 81→Glu;Phe 83→Ser; Cys 87→Ser; Asn 96→Leu or Thr; Ile 97→Thr; Lys 98→Gln; Tyr100→His; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Val 111→Met; Lys125→Gly; Val 126→Met; Ser 127→Gly or Asn; Tyr 132→Ile; Lys 134→Glu; Thr136→Ile or Val; Thr 145→Ala and Ser 146→Asn.
 10. The hNGAL mutein ofclaim 1, wherein the hNGAL mutein comprises one of the following sets ofamino acid substitutions in comparison with the linear polypeptidesequence of the mature hNGAL: (a) Gln 28→His; Leu 36→Trp; Ala 40→Thr;Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ser;Lys 73→Glu; Lys 75→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe 83→Ser;Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys 125→Gly; Tyr132→Ile; Lys 134→Glu; (b) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile41→Leu; Leu 42→Arg; Asp 47→Asn; Gln 49→Thr; Tyr 52→Gln; Ser 68→Trp; Leu70→Tyr; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe83→Ser; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys 125→Gly;Tyr 132→Ile; Lys 134→Glu; (c) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile41→Leu; Gln 49→Ile; Tyr 52→Gln; Asn 65→Asp; Ser 68→Trp; Leu 70→Tyr; Phe71→Leu; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Phe83→Ser; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Tyr 106→Ile; Lys 125→Gly;Val 126→Met; Tyr 132→Ile; Lys 134→Glu; Thr 145→Ala; (d) Gln 28→His; Leu36→Trp; Ala 40→Thr; Ile 41→Leu; Asp 47→Asn; Gln 49→Thr; Tyr 52→Gln; Val66→Ala; Ser 68→Trp; Leu 70→Tyr; Phe 71→Leu; Arg 72→Ser; Lys 73→Glu; Asp77→Asn; Trp 79→His; Arg 81→Glu; Phe 83→Ser; Cys 87→Ser; Asn 96→Thr; Ile97→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Tyr 132→Ile;Lys 134→Glu; (e) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln49→Ile; Tyr 52→Gln; Thr 54→Ile; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn;Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser 146→Asn; (f) Gln 28→His; Leu36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Pro; Tyr 52→Gln; Lys 62→Arg; Ser68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg81→Glu; Phe 83→Ser; Cys 87→Ser; Asn 96→Thr; Lys 98→Gln; Tyr 100→His; Leu103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Val 126→Met; Ser127→Gly; Tyr 132→Ile; Lys 134→Glu; (g) Gln 28→His; Leu 36→Trp; Ala40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Asp 77→Asn; Trp 79→His; Arg81→Glu; Cys 87→Ser; Asn 96→Leu; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile;Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser146→Asn; (h) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala;Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr;Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr132→Ile; Lys 134→Glu; Thr 136→Ile; Ser 146→Asn; (i) Gln 28→His; Leu36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Lys; Lys62→Arg; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Asp 77→Asn; Trp79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro;Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr136→Ile; Ser 146→Asn; (j) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Lys; Lys 62→Arg; Ser 68→Trp; Leu70→Tyr; Arg 72→Ala; Lys 73→Asp; Asp 77→Arg; Trp 79→His; Arg 81→Glu; Cys87→Ser; Asn 96→Thr; Tyr 100→His; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile;Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Ile; Ser146→Asn; (k) Gln 28→His; Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile;Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp;Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu;Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys134→Glu; Thr 136→Val; Ser 146→Asn; or (l) Gln 28→His; Leu 36→Trp; Ala40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Ile; Lys 62→Arg; Ser68→Trp; Leu 70→Tyr; Arg 72→Ser; Lys 73→Glu; Asp 77→Asn; Trp 79→His; Arg81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile;Val 111→Met; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr136→Ile; Ser 146→Asn.
 11. The hNGAL mutein of claim 1, wherein the hNGALmutein comprises one of the following sets of amino acid substitutionsin comparison with the linear polypeptide sequence of the mature hNGAL:(a) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Arg; Asp77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys134→Glu; Thr 136→Val; Ser 146→Asn; Cys 175→Phe; (b) Leu 36→Trp; Ala40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Met; Asp 77→Asn; Trp 79→His; Arg81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile;Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser146→Asn; Cys 175→Tyr; (c) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys73→Asp; Cys 76→Leu; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn;Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys 175→Trp; (d) Leu36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Ile; Asp 77→Asn; Trp79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro;Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr136→Val; Ser 146→Asn; Cys 175→Glu; (e) Leu 36→Trp; Ala 40→Thr; Ile41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg72→Ala; Lys 73→Asp; Cys 76→Val; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly;Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys175→Tyr; (f) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln;Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Arg;Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu;Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys134→Glu; Thr 136→Val; Ser 146→Asn; Cys 175→Trp; (g) Leu 36→Trp; Ala40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Asn; Asp 77→Asn; Trp 79→His; Arg81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile;Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser146→Asn; Cys 175→Leu; (h) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys73→Asp; Cys 76→Arg; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn;Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys 175→Val; (i) Leu36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys 76→Lys; Asp 77→Asn; Trp79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro;Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu: Thr136→Val; Ser 146→Asn; Cys 175→Asp; or (j) Leu 36→Trp; Ala 40→Thr; Ile41→Leu; Gln 49→Ile; Tyr 52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg72→Ala; Lys 73→Asp; Cys 76→Phe; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys87→Ser; Asn 96→Thr; Leu 103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly;Ser 127→Asn; Tyr 132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys175→Asp.
 12. The hNGAL mutein of claim 1, wherein the amino acidsequence of the hNGAL mutein further comprises the followingsubstitution in comparison with the linear polypeptide sequence of themature hNGAL: Gln 28→His; Leu 36→Arg; Gly 38→Ala; Ala 40→Asp or Glu; Ile41→Val, Thr, Ala, Arg or Glu; Glu 44→Lys or Asp; Lys 46→Asn; Gln 49→Glu;Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe 71→Leu; Arg 72→Val or Ser; Lys73→Arg, Glu or Gln; Lys 75→Arg; Asp 77→Met or Ile; Trp 79→Val; Ile80→Val or Thr; Arg 81→His; Cys 87→Ser or Gly; Lys 98→Glu; Leu 103→Val orThr; Tyr 106→Ala or Gly; Val 108→Ile; Ser 112→Asn; Asn 114→Asp; Phe123→Val; Lys 125→Leu or Val; Ser 127→Gly, Arg or Lys; Asn 129→Ser; Tyr132→Leu or Ser; Lys 134→Glu and Ile 135→Val.
 13. The hNGAL mutein ofclaim 1, wherein the hNGAL mutein comprises one of the following sets ofamino acid substitutions in comparison with the linear polypeptidesequence of the mature hNGAL: (a) Gln 28→His; Leu 36→Arg; Ala 40→Glu;Ile 41→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Ser; Lys 73→Glu;Asp 77→Ile; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr106→Ala; Lys 125→Val; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; (b) Gln28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Ala; Gln 49→Glu; Tyr 52→Glu; Ser68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Arg81→His; Cys 87→Ser; Leu 103→Val; Tyr 106→Ala; Lys 125→Leu; Ser 127→Lys;Tyr 132→Leu; Lys 134→Glu; (c) Gln 28→His; Leu 36→Arg; Gly 38→Ala; Ala40→Asp; Ile 41→Arg; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg72→Ser; Lys 73→Arg; Asp 77→Ile; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu103→Thr; Tyr 106→Gly; Lys 125→Val; Ser 127→Gly; Tyr 132→Ser; Lys134→Glu; (d) Gln 28→His; Leu 36→Arg; Ala 40→Asp: Ile 41→Glu; Gln 49→Glu;Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Asp 77→Met;Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr 106→Gly; Lys125→Val; Ser 127→Arg; Tyr 132→Leu; Lys 134→Glu; (e) Gln 28→His; Leu36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala;Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys134→Glu; (f) Gln 28→His; Leu 36→Arg; Gly 38→Ala; Ala 40→Asp; Ile 41→Val;Glu 44→Asp; Lys 46→Asn; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly;Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Ile 80→Val; Arg 81→His;Cys 87→Ser; Leu 103→Val; Tyr 106→Ala; Lys 125→Leu; Ser 127→Lys; Tyr132→Leu; Lys 134→Glu; Ile 135→Val; (g) Gln 28→His; Leu 36→Arg; Ala40→Asp; Ile 41→Thr; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe71→Leu; Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys87→Ser; Leu 103→Val; Tyr 106→Ala: Phe 123→Val; Lys 125→Leu; Ser 127→Lys;Asn 129→Ser; Tyr 132→Leu; Lys 134→Glu; (h) Gln 28→His; Leu 36→Arg; Ala40→Asp; Ile 41→Thr; Glu 44→Lys; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu70→Gly; Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys87→Ser; Leu 103→Val; Tyr 106→Ala; Phe 123→Val; Lys 125→Leu; Ser 127→Lys;Tyr 132→Leu; Lys 134→Glu; (i) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile41→Ala; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys 87→Ser; Leu 103→Val; Tyr106→Ala; Val 108→Ile; Ser 112→Asn; Phe 123→Val; Lys 125→Leu; Ser127→Lys; Tyr 132→Leu; Lys 134→Glu; or (j) Gln 28→His; Leu 36→Arg; Ala40→Asp; Ile 41→Ala; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Phe71→Leu; Arg 72→Val; Lys 73→Gln; Asp 77→Met; Trp 79→Val; Arg 81→His; Cys87→Gly; Leu 103→Val; Tyr 106→Ala; Phe 123→Val; Lys 125→Leu; Ser 127→Lys;Tyr 132→Leu; Lys 134→Glu.
 14. The hNGAL mutein of claim 1, wherein thehNGAL mutein comprises one of the following sets of amino acidsubstitutions in comparison with the linear polypeptide sequence of themature hNGAL: (a) Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Cys76→Leu; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu;Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Cys 175→Ile; Ile 176→Asp; Asp177→Gly; or (b) Leu 36→Arg; Ala 40→Asp; Ile 41-3 Val; Gln 49→Glu; Tyr52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Cys76→Tyr; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu;Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Cys 175→Ile; Ile 176→Asp; Asp177→Gly.
 15. The hNGAL mutein of claim 1, wherein the amino acidsequence of the hNGAL mutein further comprises the followingsubstitution and addition in comparison with the linear polypeptidesequence of the mature hNGAL: Ile 8→Lys; Pro 9→His; Gln 28→His; Leu36→Trp or Arg; Ala 40→Thr or Asp; Ile 41→Leu or Val; Gln 49→Ile or Glu;Tyr 52→Gln or Glu; Thr 54→Met; Asn 65→Gln; Ser 68→Trp or Asp; Leu 70→Tyror Gly; Arg 72→Ala or Val; Lys 73→Asp or Gln; Lys 75→Arg; Cys 76→Ile;Asp 77→Asn or Met; Trp 79→His or Val; Ile 80→Thr; Arg 81→Glu or His; Cys87→Ser; Asn 96→Thr; Lys 98→Glu; Leu 103→Glu or Val; Ser 105→Pro; Tyr106→Ile or Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Gly or Leu; Ser127→Asn or Lys; Tyr 132→Ile or Leu; Lys 134→Glu; Thr 136→Val; Ser146→Asn; Cys 175→Glu; Gly 178→Asp and Gly is added to N-terminal aminoacid (Gln 1).
 16. The hNGAL mutein of claim 1, wherein the hNGAL muteincomprises one of the following sets of amino acid substitutions andadditions in comparison with the linear polypeptide sequence of themature hNGAL: (a) Leu 36→Trp; Ala 40→Thr; Ile 41→Leu; Gln 49→Ile; Tyr52→Gln; Thr 54→Met; Ser 68→Trp; Leu 70→Tyr; Arg 72→Ala; Lys 73→Asp; Cys76→Ile; Asp 77→Asn; Trp 79→His; Arg 81→Glu; Cys 87→Ser; Asn 96→Thr; Leu103→Glu; Ser 105→Pro; Tyr 106→Ile; Lys 125→Gly; Ser 127→Asn; Tyr132→Ile; Lys 134→Glu; Thr 136→Val; Ser 146→Asn; Cys 175→Glu and Gly isadded to N-terminal amino acid (Gln 1) (SEQ ID NO: 87); (b) Gln 28→His;Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp;Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val;Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr132→Leu; Lys 134→Glu and Gly is added to N-terminal amino acid (Gln 1)(SEQ ID NO: 88); (c) Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln49→Glu; Tyr 52→Glu; Asn 65→Gln; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val;Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Gly 178→Asp and Glyis added to N-terminal amino acid (Gln 1) (SEQ ID NO: 89); (d) Ile8→Lys; Gln 28→His; Leu 36→Arg; Ala 40-3 Asp; Ile 41→Val; Gln 49→Glu; Tyr52→Glu; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Asp77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser127→Lys; Tyr 132→Leu; Lys 134→Glu and Gly is added to N-terminal aminoacid (Gln 1) (SEQ ID NO: 90); (e) Pro 9→His; Gln 28→His; Leu 36→Arg; Ala40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu; Ser 68→Asp; Leu 70→Gly; Arg72→Val; Lys 73→Gln; Lys 75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg81→His; Cys 87→Ser; Lys 98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp;Phe 123→Val; Lys 125→Leu; Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu and Glyis added to N-terminal amino acid (Gln 1) (SEQ ID NO: 91); (f) Ile8→Lys: Gln 28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr52→Glu; Asn 65→Gln; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys75→Arg; Asp 77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys98→Glu; Leu 103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu;Ser 127→Lys; Tyr 132→Leu; Lys 134→Glu; Gly 178→Asp and Gly is added toN-terminal amino acid (Gln 1) (SEQ ID NO: 92); or (g) Pro 9→His; Gln28→His; Leu 36→Arg; Ala 40→Asp; Ile 41→Val; Gln 49→Glu; Tyr 52→Glu; Asn65→Gln; Ser 68→Asp; Leu 70→Gly; Arg 72→Val; Lys 73→Gln; Lys 75→Arg; Asp77→Met; Trp 79→Val; Ile 80→Thr; Arg 81→His; Cys 87→Ser; Lys 98→Glu; Leu103→Val; Tyr 106→Ala; Asn 114→Asp; Phe 123→Val; Lys 125→Leu; Ser127→Lys; Tyr 132→Leu; Lys 134→Glu; Gly 178→Asp and Gly is added toN-terminal amino acid (Gln 1) (SEQ ID NO: 93).
 17. The hNGAL mutein ofclaim 1, wherein the hNGAL mutein comprises an amino acid sequenceselected from the group consisting of SEQ ID NOs: 2-40, 87-93 andfunctional fragments or variants thereof.
 18. The hNGAL mutein of claim1, wherein said hNGAL mutein comprises at least one amino acidsubstitution of a native cysteine residue by another amino acid.
 19. Anucleic acid molecule comprising a nucleotide sequence encoding thehNGAL mutein of claim
 1. 20. A host cell containing a nucleic acidmolecule of claim
 19. 21. A method of producing a hNGAL mutein, whereinthe polypeptide is produced starting from the nucleic acid coding forthe polypeptide by means of genetic engineering methods, wherein thepolypeptide is produced in the host cell of claim 20 and is isolatedfrom the host cell or its culture.
 22. A pharmaceutical compositioncomprising the hNGAL mutein of claim 1 for treating, preventing orameliorating a disease or disorder associated with deregulated proteinplasma extravasation in a subject.
 23. A method of binding CGRP in asubject comprising administering to said subject the hNGAL mutein ofclaim
 1. 24. A method for inhibiting or reducing migraines or plasmaprotein extravasation in a subject, comprising administering to saidsubject an effective amount of the hNGAL mutein of claim
 1. 25. A methodof treating, preventing or ameliorating a disease or disorder associatedwith deregulated protein plasma extravasation in a subject, comprisingadministering to said subject an effective amount of the hNGAL mutein ofclaim 1.